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                                                                     EXHIBIT 1.1

                               5,760,000 Shares

                                TELEGROUP, INC.

                                 Common Stock

                                   FORM OF 

                          U.S. UNDERWRITING AGREEMENT


                                June    , 1997


SMITH BARNEY INC.
Alex. Brown & Sons Incorporated
COWEN & COMPANY

     As Representatives of the Several Underwriters

c/o  SMITH BARNEY INC.
     388 Greenwich Street
     New York, New York 10013

Dear Sirs:

          Telegroup, Inc., an Iowa corporation (the "Company"), proposes to
issue and sell an aggregate of 5,760,000 shares of its common stock, no par
value per share (the "Firm Shares") to the several U.S. Underwriters named in
Schedule I hereto (the "U.S. Underwriters") for whom Smith Barney Inc., Alex.
Brown & Sons Incorporated and Cowen & Company are acting as representatives
(the "Representatives").  In addition, solely for the purpose of covering
over-allotments, the persons named in Schedule II hereto (the "Selling
Shareholders") propose to sell to the U.S. Underwriters, upon the terms and
conditions set forth in Section 2 hereof, up to an additional 864,000 shares
(the "Additional Shares") of the common stock of the Company.  The Company and
the Selling Shareholders are hereinafter sometimes referred to as the
"Sellers."  590,001 of the Additional Shares to be sold by Greenwich Street
Capital Partners, L.P., Greenwich Street Capital Offshore Fund, Ltd., TRV
Employees Fund, L.P., The Travelers Insurance Company and The Travelers Life
and Annuity Company (collectively the "Greenwich Street Affiliates"), are
issuable upon exercise of warrants to purchase common stock of the Company
(the "Warrants").  Each Warrant entitles the holder thereof to purchase       
shares of Common Stock (as defined herein) at an exercise price of $0.01 per
share.  The Firm Shares and the Additional Shares are hereinafter collectively
referred to as the "Shares."  The Company's common stock, no par value per
share, including the Shares and the International Shares (as defined herein),
is hereinafter referred to as the "Common Stock."
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          It is understood that the Company and the Selling Shareholders are
concurrently entering into an International Underwriting Agreement, dated the
date hereof (the "International Underwriting Agreement"), providing for the
sale of 1,440,000 shares of the Common Stock (the "Firm International Shares")
by the Company (plus an option granted by the Selling Shareholders to purchase
up to an additional 216,000 shares of Common Stock (the "Additional
International Shares") solely for the purpose of covering over-allotments)
through arrangements with certain underwriters outside the United States and
Canada (the "Managers"), for whom Smith Barney Inc.,  Alex. Brown & Sons
Incorporated and Cowen & Company are acting as lead Managers (the "Lead
Managers"). All shares of Common Stock proposed to be offered to the Managers
pursuant to the International Underwriting Agreement, including the Firm
International Shares and the Additional International Shares, are herein
referred to as the "International Shares;" the International Shares and the
Shares, collectively, are herein referred to as the "Underwritten Shares."

          The Company and the Selling Shareholders also understand that the
Representatives and the Lead Managers have entered into an agreement (the
"Agreement Between U.S. Underwriters and Managers") contemplating the
coordination of certain transactions between the U.S. Underwriters and the
Managers and that, pursuant thereto and subject to the conditions set forth
therein, the U.S. Underwriters may purchase from the Managers a portion of the
International Shares or sell to the Managers a portion of the Shares.  The
Company and the Selling Shareholders understand that any such purchases and
sales between the U.S. Underwriters and the Managers shall be governed by the
Agreement Between U.S. Underwriters and Managers and shall not be governed by
the terms of this Agreement or the International Underwriting Agreement.

          The Company and the Selling Shareholders wish to confirm as follows
their respective agreements with you and the other several U.S. Underwriters
on whose behalf you are acting, in connection with the several purchases of
the Shares by the U.S. Underwriters. 

     1.     REGISTRATION STATEMENT AND PROSPECTUS.  The Company has prepared
and filed with the Securities and Exchange Commission (the "Commission") in
accordance with the provisions of the Securities Act of 1933, as amended, and
the rules and regulations of the Commission thereunder (collectively, the
"Act"), a registration statement on Form S-1, including prospectuses subject
to completion, relating to the Underwritten Shares.  The term "Registration
Statement" as used in this Agreement means the registration statement
(including all financial schedules and exhibits), as amended at the time it
becomes effective, and as thereafter amended by post-effective amendment.  The
term "Prospectuses" as used in this Agreement means the prospectuses in the
forms included in the Registration Statement, or, if the

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prospectuses included in the Registration Statement omit information in
reliance on Rule 430A under the Act and such information is included in
prospectuses filed with the Commission pursuant to Rule 424(b) under the Act,
the term "Prospectuses" as used in this Agreement means the prospectuses in
the forms included in the Registration Statement as supplemented by the
addition of the Rule 430A information contained in the prospectuses filed with
the Commission pursuant to Rule 424(b).  The term "Prepricing Prospectuses" as
used in this Agreement means the prospectuses subject to completion in the
forms included in the Registration Statement at the time of the initial filing
of the Registration Statement with the Commission, and as such prospectuses
shall have been amended from time to time prior to the date of the
Prospectuses.

          It is understood that two forms of Prepricing Prospectus and two
forms of Prospectus are to be used in connection with the offering and sale of
the Underwritten Shares:  a Prepricing Prospectus and a Prospectus relating to
the Shares that are to be offered and sold in the United States (as defined
herein) or Canada (as defined herein) to U.S. or Canadian Persons (the "U.S.
Prepricing Prospectus" and the "U.S. Prospectus," respectively), and a
Prepricing Prospectus and a Prospectus relating to the International Shares
which are to be offered and sold outside the United States or Canada to
persons other than U.S. or Canadian Persons (the "International Prepricing
Prospectus" and the "International Prospectus," respectively).  The U.S.
Prospectus and the International Prospectus are herein collectively called the
"Prospectuses," and the U.S. Prepricing Prospectus and the International
Prepricing Prospectus are herein called the "Prepricing Prospectuses."  For
purposes of this Agreement, "Exchange Act" means the Securities Exchange Act
of 1934, as amended, and the rules and regulations of the Commission
thereunder.  "U.S. or Canadian Person" means any resident or national of the
United States or Canada, any corporation, partnership or other entity created
or organized in or under the laws of the United States or Canada or any estate
or trust the income of which is subject to United States or Canadian income
taxation regardless of the source of its income (other than the foreign branch
of any U.S. or Canadian Person), and includes any United States or Canadian
branch of a person other than a U.S. or Canadian Person; "United States" means
the United States of America (including the states thereof and the District of
Columbia) and its territories, its possessions and other areas subject to its
jurisdiction; and "Canada" means Canada and its territories, its possessions
and other areas subject to its jurisdiction.

     2.     Agreements to Sell and Purchase.  Upon the basis of the
representations, warranties and agreements contained herein and subject to all
the terms and conditions set forth herein and to such adjustments as you may
determine to avoid fractional shares, the Company hereby agrees to issue and
sell to each U.S. Underwriter and each U.S. Underwriter agrees, severally and
not
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jointly, to purchase from the Company, at a purchase price of [$           ]
per share (the "purchase price per share"), the number of Firm Shares that
bears the same proportion to the aggregate number of Firm Shares to be issued
and sold by the Company as the number of Firm Shares set forth opposite the
name of such Underwriter in Schedule I hereto (or such number of Firm Shares
increased as set forth in Section 12 hereof) bears to the aggregate number of
Firm Shares to be sold by the Company. 

          Upon the basis of the representations, warranties and agreements
contained herein and subject to all the terms and conditions set forth herein,
the Selling Shareholders listed in Schedule II hereto agree to sell to the
U.S. Underwriters, and the U.S. Underwriters shall have the right to purchase
from such Selling Shareholders listed in Schedule II hereto, at the purchase
price per share, pursuant to an option (the "over-allotment option") which may
be exercised prior to 5:00 p.m., New York City time, on the 30th day after the
date of the U.S. Prospectus (or, if such 30th day shall be a Saturday or
Sunday or a holiday, on the next business day thereafter when the New York
Stock Exchange is open for trading), up to an aggregate of 864,000 Additional
Shares from the Selling Shareholders listed in Schedule II hereto (the maximum
number of Additional Shares that each of them agrees to sell upon the exercise
by the U.S. Underwriters of the over-allotment option is set forth opposite
their respective names in Schedule II).  The number of Additional Shares that
the U.S. Underwriters elect to purchase upon any exercise of the
over-allotment option shall be provided by each Selling Shareholder who has
agreed to sell Additional Shares in proportion to the respective maximum
numbers of Additional Shares that each such Selling Shareholder has agreed to
sell.  Additional Shares may be purchased only for the purpose of covering
over-allotments made in connection with the offering of the Firm Shares.  Upon
any exercise of the over-allotment option, each U.S. Underwriter, severally
and not jointly, agrees to purchase from each Selling Shareholder who has
agreed to sell Additional Shares, the number of Additional Shares (subject to
such adjustments as you may determine in order to avoid fractional shares)
that bears the same proportion to the number of Additional Shares to be sold
by each Selling Shareholder who has agreed to sell Additional Shares as the
number of Firm Shares set forth opposite the name of such U.S. Underwriter in
Schedule I hereto (or such number of Firm Shares increased as set forth in
Section 12 hereof) bears to the aggregate number of Firm Shares to be sold by
the Company. 

          Certificates in transferable form for the Additional Shares that
each of Fred Gratzon and Shelley L. Levin-Gratzon as joint tenants (each of
Fred Gratzon and Shelly L. Levin-Gratzon, collectively the "Gratzons") and
Clifford Rees agrees to sell pursuant to this Agreement have been placed in
custody with Swidler & Berlin, Chartered (the "Custodian") for delivery under
this Agreement pursuant to a Custody Agreement and Power of Attorney (the "GR
Custody Agreement") executed by each of the Gratzons and

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Clifford Rees appointing [           ] and [           ] as agents and
attorneys-in-fact (the "Attorneys-in-Fact").  Each of the Gratzons and
Clifford Rees agrees that (i) the Additional Shares represented by the
certificates held in custody pursuant to the GR Custody Agreement are subject
to the interests of the U.S. Underwriters, the Company and each other Selling
Shareholder, (ii) the arrangements made by the Gratzons and Clifford Rees for
such custody are, except as specifically provided in the GR Custody Agreement,
irrevocable, and (iii) the obligations of the Gratzons and Clifford Rees
hereunder and under the GR Custody Agreement shall not be terminated by any
act of such Selling Shareholder or by operation of law, whether by the death
or incapacity of any of the Gratzons or Clifford Rees or the occurrence of any
other event. If any of the Gratzons or Clifford Rees shall die or be
incapacitated or if any other event shall occur before the delivery of the
Additional Shares of the Gratzons and Clifford Rees to be sold hereunder,
certificates for the Additional Shares of such Selling Shareholder shall be
delivered to the U.S. Underwriters by the Attorneys-in-Fact in accordance with
the terms and conditions of this Agreement and the GR Custody Agreement as if
such death or incapacity or other event had not occurred, regardless of
whether or not the Attorneys-in-Fact or any U.S. Underwriter shall have
received notice of such death, incapacity or other event.  Each
Attorney-in-Fact is authorized, on behalf of each of the Gratzons and Clifford
Rees, to execute this Agreement and any other documents necessary or desirable
in connection with the sale of the Additional Shares to be sold hereunder by
the Gratzons and Clifford Rees, to make delivery of the certificates for such
Additional Shares, to receive the proceeds of the sale of such Additional
Shares, to give receipts for such proceeds, to pay therefrom any expenses to
be borne by the Gratzons and Clifford Rees in connection with the sale and
public offering of such Additional Shares, to distribute the balance thereof
to the Gratzons and Clifford Rees, and to take such other action as may be
necessary or desirable in connection with the transactions contemplated by
this Agreement.  Each Attorney-in-Fact agrees to perform his duties under the
GR Custody Agreement.

          Certificates in transferable form for the Additional Shares that
each of Steve Rubin and Steve Foster agrees to sell pursuant to this Agreement
have been placed in custody with the Custodian for delivery under this
Agreement pursuant to a Custody Agreement and Power of Attorney (the "RF
Custody Agreement") executed by Mr. Rubin and Mr. Foster appointing
[           ] and [           ] as agents and attorneys-in-fact (the "RF
Attorneys-in-Fact").  Each of Steven Rubin and Steven Foster agrees that (i)
the Additional Shares represented by the certificates held in custody pursuant
to the RF Custody Agreement are subject to the interests of the U.S.
Underwriters, the Company and each other Selling Shareholder, (ii) the
arrangements made by Steven Rubin and Steven Foster, for such custody are,
except as specifically provided in the RF Custody Agreement, irrevocable, and
(iii) the obligations of Steven Rubin and Steven Foster hereunder and under

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the RF Custody Agreement shall not be terminated by any act of such Selling
Shareholder or by operation of law, whether by the death or incapacity of any
of Steven Rubin or Steven Foster or the occurrence of any other event. If any
of Steven Rubin or Steven Foster shall die or be incapacitated or if any other
event shall occur before the delivery of the Additional Shares of Steven Rubin
and Steven Foster to be sold hereunder, certificates for the Additional Shares
of such Selling Shareholder shall be delivered to the U.S. Underwriters by the
RF Attorneys-in-Fact in accordance with the terms and conditions of this
Agreement and the RF Custody Agreement, respectively, as if such death or
incapacity or other event had not occurred, regardless of whether or not the
respective Attorneys-in-Fact or any U.S. Underwriter shall have received
notice of such death, incapacity or other event.  The RF Attorneys-in-Fact are
authorized, on behalf of Steven Rubin and Steven Foster, to execute this
Agreement and any other documents necessary or desirable in connection with
the sale of the Additional Shares to be sold hereunder by Steven Rubin and
Steven Foster to make delivery of the certificates for such Additional Shares,
to receive the proceeds of the sale of such Additional Shares, to give
receipts for such proceeds, to pay therefrom any expenses to be borne by
Steven Rubin and Steven Foster in connection with the sale and public offering
of such Additional Shares, to distribute the balance thereof to Steven Rubin
and Steven Foster and to take such other action as may be necessary or
desirable in connection with the transactions contemplated by this Agreement. 
Each RF Attorney-in-Fact agrees to perform his duties under the RF Custody
Agreement.

          Certificates in transferable form for the Warrants which are
exercisable for the Additional Shares that the Greenwich Street Affiliates
agree to sell pursuant to this Agreement have been placed in custody with the
Custodian for delivery under this Agreement pursuant to a Custody Agreement
(the "Greenwich Street Custody Agreement" and collectively with the GR Custody
Agreement, and the RF Custody Agreement, the "Custody Agreements").  The
Greenwich Street Affiliates agree that (i) the Warrants and Additional Shares
represented by the certificates held in custody pursuant to the Greenwich
Street Custody Agreement are subject to the interests of the U.S.
Underwriters, the Company and each other Selling Shareholder, (ii) the
arrangements made by the Greenwich Street Affiliates are, except as
specifically provided in the Greenwich Street Custody Agreement, irrevocable,
and (iii) the obligations of the Greenwich Street Affiliates hereunder and
under the Greenwich Street Custody Agreement shall not be terminated by any
act of the Greenwich Street Affiliates or by operation of law, whether upon
any dissolution, winding up, distribution of assets or other event affecting
the legal existence of any of the Greenwich Street Affiliates.  If any event
shall occur before the delivery of the Additional Shares to be sold by the
Greenwich Street Affiliates hereunder or if any of the Greenwich Street 

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Affiliates shall dissolve, wind up, distribute assets or if any other event
affecting the legal existence of any of the Greenwich Street Affiliates shall
occur before the delivery of the Additional Shares to be sold by the Greenwich
Street Affiliates hereunder, the Warrants shall be exercised for the
Additional Shares to be sold by the Greenwich Street Affiliates hereunder and
certificates evidencing such Additional Shares shall be delivered to the U.S.
Underwriters by the Custodian in accordance with the terms and conditions of
this Agreement and the Greenwich Street Custody Agreement as if such
dissolution, winding up or distribution of assets or other event had not
occurred, regardless of whether or not any U.S. Underwriter shall have
received notice of such dissolution, winding up or distribution of assets or
other event.

          Each U.S. Underwriter represents, warrants, covenants and agrees
that, except as contemplated under Section 2 of the Agreement Between U.S.
Underwriters and Managers dated the date hereof, (i) it is not purchasing any
Shares for the account of anyone other than a U.S. or Canadian Person, (ii) it
has not offered or sold, and will not offer, sell, resell or deliver, directly
or indirectly, any Shares or distribute any U.S. Prepricing Prospectus or U.S.
Prospectus outside the United States or Canada or to anyone other than a U.S.
or Canadian Person, and (iii) any offer of Shares in Canada will be made only
pursuant to an exemption from the requirement to file a prospectus in the
relevant province of Canada in which such offer is made.

     3.     Terms of Public Offering.  The Sellers have been advised by you
that the U.S. Underwriters propose to make a public offering of their
respective portions of the Shares as soon after the Registration Statement and
this Agreement have become effective as in your judgment is advisable and
initially to offer the Shares upon the terms set forth in the U.S. Prospectus. 

     4.     Delivery of the Shares and Payment Therefor.  Delivery to the U.S.
Underwriters of and payment for the Firm Shares shall be made at the office of
Smith Barney Inc., 388 Greenwich Street, New York, NY 10013, at 10:00 A.M.,
New York City time, on [           ], 1997 (the "Closing Date").  The place of
closing for the Firm Shares and the Closing Date may be varied by agreement
among you, the Company and the Attorneys-in-Fact.

          Delivery to the U.S. Underwriters of and payment for any Additional
Shares to be purchased by the U.S. Underwriters shall be made at the
aforementioned office of Smith Barney Inc. at such time on such date (the
"Option Closing Date"), which may be the same as the Closing Date but shall in
no event be earlier than the Closing Date nor earlier than two nor later than
ten business days after the giving of the notice hereinafter referred to, as
shall be specified in a written notice from you on behalf of the U.S.
Underwriters to the Attorneys-in-Fact of the U.S. Underwriters' determination
to purchase a number, specified in such notice, of Additional Shares.  The
place of closing for any Additional Shares and the Option Closing Date, if
any, for such Shares may be varied by agreement between you and the
Attorneys-in-Fact. 

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          Certificates for the Firm Shares and for any Additional Shares to be
purchased hereunder shall be registered in such names and in such
denominations as you shall request by written notice, it being understood that
a facsimile transmission shall be deemed written notice, prior to 9:30 A.M.,
New York City time, on the second business day preceding the Closing Date or
the Option Closing Date, as the case may be.  Such certificates shall be made
available to you in New York City for inspection and packaging not later than
9:30 A.M., New York City time, on the business day next preceding the Closing
Date or the Option Closing Date, as the case may be.  The certificates and
stock powers evidencing the Firm Shares and any Additional Shares to be
purchased hereunder shall be delivered to you on the Closing Date or the
Option Closing Date, as the case may be, against payment of the purchase price
therefor in immediately available funds.

     5.     Agreements of the Company.  The Company agrees with the several
U.S. Underwriters as follows:

          (a)  If, at the time this Agreement is executed and delivered, it is
necessary for the Registration Statement or a post-effective amendment thereto
to be declared effective before the offering of the Shares may commence, the
Company will endeavor to cause the Registration Statement or such
post-effective amendment to become effective as soon as possible and will
advise you promptly and, if requested by you, will confirm such advice in
writing, when the Registration Statement or such post-effective amendment has
become effective. 

          (b)  The Company will advise you promptly and, if requested by you,
will confirm such advice in writing:  (i) of any request by the Commission of
which the Company has knowledge for amendment of or a supplement to the
Registration Statement, any Prepricing Prospectuses or the Prospectuses or for
additional information; (ii) of the issuance by the Commission of any stop
order suspending the effectiveness of the Registration Statement or of the
suspension of qualification of the Shares for offering or sale in any
jurisdiction or the initiation of any proceeding for such purpose of which the
Company has knowledge; and (iii) within the period of time referred to in
paragraph (f) below, of any change in the Company's condition (financial or
other), business, prospects, properties, net worth or results of operations,
or of the happening of any event, including the filing of any information,
documents or reports pursuant to the Exchange Act, that makes any statement of
a material fact made in the Registration Statement or the Prospectuses (as
then amended or supplemented) untrue or which requires the making of any
additions to or changes in the Registration Statement or the Prospectuses (as
then amended or supplemented) in order to state a material fact required by
the Act to be stated therein or necessary in order to make the statements
therein not misleading, or of the necessity to amend or supplement the
Prospectuses (as then amended or

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supplemented) to comply with the Act or any other law.  If at any time the
Commission shall issue any stop order suspending the effectiveness of the
Registration Statement, the Company will make every reasonable effort to
obtain the withdrawal of such order at the earliest possible time. 

          (c)  The Company will furnish to you, without charge, four (4)
signed copies of the Registration Statement as originally filed with the
Commission and of each amendment thereto, including financial statements and
all exhibits to the Registration Statement and will also furnish to you,
without charge, such number of conformed copies of the Registration Statement
as originally filed and of each amendment thereto, but without exhibits, as
you may reasonably request.

          (d)  The Company will not (i) file any amendment to the Registration
Statement or make any amendment or supplement to the Prospectuses of which you
shall not previously have been advised or to which you shall reasonably object
in writing after being so advised or (ii) so long as, in the written opinion
of counsel for the U.S. Underwriters (a copy of which shall be delivered to
the Company), a prospectus is required to be delivered in connection with
sales by any U.S. Underwriter or dealer, file any information, documents or
reports pursuant to the Exchange Act, without delivering a copy of such
information, documents or reports to you, as Representatives of the U.S.
Underwriters, prior to or concurrently with such filing.

          (e)  Prior to the execution and delivery of this Agreement, the
Company has delivered or will deliver to you, without charge, in such
quantities as you have reasonably requested or may hereafter reasonably
request, copies of each form of the U.S. Prepricing Prospectus.  The Company
consents to the use, in accordance with the provisions of the Act and with the
securities or Blue Sky laws of the jurisdictions in which the Shares are
offered by the several U.S. Underwriters and by dealers, prior to the date of
the U.S. Prospectus, of each U.S. Prepricing Prospectus so furnished by the
Company. 

          (f)  As soon after the execution and delivery of this Agreement as
possible and thereafter from time to time for such period as in the written
opinion of counsel for the U.S. Underwriters (a copy of which shall be
delivered to the Company) a U.S. Prospectus is required by the Act to be
delivered in connection with sales by any U.S. Underwriter or dealer, the
Company will expeditiously deliver to each U.S. Underwriter and each dealer,
without charge, as many copies of the U.S. Prospectus (and of any amendment or
supplement thereto) as you may reasonably request.  The Company consents to
the use of the U.S. Prospectus (and of any amendment or supplement thereto) in
accordance with the provisions of the Act and with the securities or Blue Sky
laws of the jurisdictions in which the Shares are offered by the several U.S.
Underwriters and by all dealers to whom Shares may be sold,

                                      9
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both in connection with the offering and sale of the Shares and for such
period of time thereafter as the U.S. Prospectus is required by the Act to be
delivered in connection with sales by any U.S. Underwriter or dealer.  If
during such period of time any event shall occur that in the judgment of the
Company or in the written opinion of counsel for the U.S. Underwriters (a copy
of which shall be delivered to the Company) is required to be set forth in the
U.S. Prospectus (as then amended or supplemented) or should be set forth
therein in order to make the statements therein, in the light of the
circumstances under which they were made, not misleading, or if it is
necessary to supplement or amend the U.S. Prospectus to comply with the Act or
any other law, the Company will forthwith prepare and, subject to the
provisions of paragraph (d) above, file with the Commission an appropriate
supplement or amendment thereto and will expeditiously furnish to the U.S.
Underwriters and dealers a reasonable number of copies thereof.  

          (g)  The Company will cooperate with you and with counsel for the
U.S. Underwriters in connection with the registration or qualification of the
Shares for offering and sale by the several U.S. Underwriters and by dealers
under the securities or Blue Sky laws of such jurisdictions as you may
reasonably designate and will file such consents to service of process or
other documents necessary or appropriate in order to effect such registration
or qualification; provided that in no event shall the Company be obligated to
qualify to do business in any jurisdiction where it is not now so qualified or
to take any action that would subject it to service of process in suits, other
than those arising out of the offering or sale of the Shares, in any
jurisdiction where it is not now so subject. 

          (h)  The Company will make generally available to its security
holders a consolidated earnings statement, which need not be audited, covering
a twelve-month period commencing after the effective date of the Registration
Statement and ending not later than 15 months thereafter, as soon as
reasonably practicable after the end of such period, which consolidated
earnings statement shall satisfy the provisions of Section 11(a) of the Act.

          (i)  During the period of five years hereafter, the Company will
furnish to you (i) as soon as available, a copy of each report of the Company
mailed to stockholders or filed with the Commission or the Nasdaq National
Market, and (ii) from time to time such other information concerning the
Company as you may reasonably request.

          (j)  If this Agreement shall terminate or shall be terminated after
execution pursuant to any provisions hereof (otherwise than pursuant to the
second paragraph of Section 12 hereof or by notice given by you terminating
this Agreement pursuant to Section 12 or Section 13 hereof) or if this
Agreement shall be terminated by the U.S. Underwriters because of any failure
or refusal on the part of the Company or any of the Selling

                                      10
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Shareholders to comply, in any material respect, with the terms or fulfill, in
any material respect, any of the conditions of this Agreement, the Company
agrees to reimburse the Representatives for all reasonable out-of-pocket
expenses (including reasonable fees and expenses of counsel for the U.S.
Underwriters) incurred by you in connection herewith. 

          (k)  The Company will apply the net proceeds from the sale of the
Shares to be sold by it hereunder substantially in accordance with the
description set forth in the Prospectuses. 

          (l)  If Rule 430A of the Act is employed, the Company will timely
file the Prospectuses pursuant to Rule 424(b) under the Act and will advise
you of the time and manner of such filing. 

          (m)  For a period of 180 days after the date hereof (the "Lock-up
Period"), the Company will not, without the prior written consent of Smith
Barney Inc., offer, sell, contract to sell or otherwise dispose of any Common
Stock (or any securities convertible into or exercisable or exchangeable for
Common Stock) or grant any options or warrants to purchase Common Stock,
except for (i) the Company's issuance of shares of Common Stock in connection
with the reclassification of its Common Stock, (ii) the Company's issuance of
shares of its Common Stock in connection with the approximate 5.51-for-1 stock
split, (iii) the Company's issuance of shares of Common Stock upon exercise of
the Warrants, (iv) the issuance of Common Stock upon the exercise of stock
options granted, or the grant of stock options under the Company's Stock
Option Plan (and the filing of a Form S-8 Registration Statement with respect
to such shares of Common Stock) and (v) sales to the U.S. Underwriters
pursuant to this Agreement and the Managers pursuant to the International
Underwriting Agreement. 

          (n)  The Company has furnished or will furnish to you "lock-up"
letters, in form and substance reasonably satisfactory to you, signed by each
of its current officers and directors and each of ___________.

          (o)  Except as stated in this Agreement and in the International
Underwriting Agreement and in the Prepricing Prospectuses and Prospectuses,
the Company has not taken, nor will it take, directly or indirectly, any
action designed to or that might reasonably be expected to cause or result in
stabilization or manipulation of the price of the Common Stock to facilitate
the sale or resale of the Shares.

          (p)  The Company will use its reasonable best efforts to have the
Common Stock listed, subject to notice of issuance, on the Nasdaq National
Market concurrently with the effectiveness of the registration statement.

                                     11
<PAGE>
 
     6.     Agreements of the Selling Shareholders.  Each of the Selling
Shareholders agrees, severally and not jointly, with the several U.S.
Underwriters as follows:

          (a)     Messrs. Gratzon and Rees will cooperate to the extent
necessary to cause the registration statement or any post-effective amendment
thereto to become effective at the earliest possible time and each of the
other Selling Shareholders will cooperate to the extent necessary in
furnishing all information with respect to itself of a type referred to in
Item 507 of Regulation S-K under the Act so as to permit the registration
statement or any post effective amendment thereto to become effective at the
earliest possible time. 

          (b)     Such Selling Shareholder will pay all Federal and other
taxes, if any on the transfer or sale of such Additional Shares that are sold
by the Selling Shareholder to the U.S. Underwriters. 

          (c)     Such Selling Shareholder will do or perform all things
required to be done or performed by the Selling Shareholder under this
Agreement prior to the Closing Date or any Option Closing Date, as the case
may be, to satisfy all conditions precedent to the delivery of the Additional
Shares pursuant to this Agreement. 

          (d)     For a period of 180 days after the date hereof, such Selling
Shareholder will not, without the prior written consent of Smith Barney Inc.,
offer, sell, contract to sell or otherwise dispose of any Common Stock (or any
securities convertible into or exercisable or exchangeable for Common Stock)
or grant any options or warrants to purchase Common Stock, except for the sale
of Additional Shares to the Underwriters pursuant to this Agreement and sale
to the Managers under the International Underwriting Agreement.

          (e)     Except as stated in this Agreement and the International
Underwriting Agreement and in the Prepricing Prospectuses and the
Prospectuses, such Selling Shareholder has not taken, nor will it take,
directly or indirectly, any action designed to or that might reasonably be
expected to cause or result in stabilization or manipulation of the price of
the Common Stock to facilitate the sale or resale of the Shares. 

          (f)     Such Selling Shareholder will advise you promptly upon
becoming aware, and if requested by you, will confirm such advice in writing,
within the period of time referred to in Section 5(f) hereof, of any change in
the Company's condition (financial or other), business, prospects, properties,
net worth or results of operations, or of the happening of any event that
makes any statement of material fact made in the Registration Statement or the
Prospectuses (as then amended or supplemented) untrue or which requires the
making of any additions to or changes in the

                                    12
<PAGE>
 
Registration Statement or the Prospectuses (as then amended or supplemented)
in order to state a material fact required by the Act to be stated therein or
necessary in order to make the statements therein not misleading, or of the
necessity to amend or supplement the Prospectuses (as then amended or
supplemented) to comply with the Act or any other law.

     7.     Representations and Warranties of the Company, Fred Gratzon and
Clifford Rees.  Each of the Company, Fred Gratzon, and Clifford Rees
represents and warrants to each U.S. Underwriter that:

          (a)  Each U.S. Prepricing Prospectus included as part of the
registration statement as originally filed or as part of any amendment or
supplement thereto, or filed pursuant to Rule 424 under the Act, complied when
so filed in all material respects with the provisions of the Act; except that
this representation and warranty does not apply to statements in or omissions
from such U.S. Prepricing Prospectus (or any amendment or supplement thereto)
made in reliance upon and in conformity with information relating to any U.S.
Underwriter or Manager furnished to the Company in writing by a U.S.
Underwriter through the Representatives or by a Manager through the Lead
Managers expressly for use therein.  The Commission has not issued any order
preventing or suspending the use of any Prepricing Prospectus. 

          (b)  The Registration Statement in the form in which it became or
becomes effective and also in such form as it may be when any post-effective
amendment thereto shall become effective and the Prospectuses and any
supplement or amendment thereto when filed with the Commission under Rule
424(b) under the Act, complied or will comply in all material respects with
the provisions of the Act and will not at any such time contain an untrue
statement of a material fact or omit to state a material fact required to be
stated therein or necessary to make the statements therein not misleading;
except that this representation and warranty does not apply to statements in
or omissions from the Registration Statement or the Prospectuses made in
reliance upon and in conformity with information relating to any U.S.
Underwriter or Manager furnished to the Company in writing by or on behalf of
a U.S. Underwriter through the Representatives or by or on behalf of a Manager
through the Lead Managers expressly for use therein. 

          (c)  All the outstanding shares of Common Stock of the Company
(including the Additional Shares to be sold by the Gratzons and Clifford Rees)
have been duly authorized and validly issued, are fully paid and nonassessable
and are free of any preemptive or similar rights; the Firm Shares to be issued
and sold by the Company have been duly authorized and, when issued and
delivered to the U.S. Underwriters against payment therefor in accordance with
the terms hereof, will be validly issued, fully paid and nonassessable and
free of any preemptive or similar rights; the Additional Shares issuable upon
exercise of the Warrants have been

                                     13
<PAGE>
 
duly authorized for issuance and, when issued and delivered to the Greenwich
Street Affiliates by the Company upon exercise of the Warrants against payment
of the exercise price therefor, will be validly issued, fully paid and
nonassessable and free of any preemptive or similar rights; and the capital
stock of the Company conforms in all material respects to the description
thereof in the Registration Statement and the Prospectuses.

          (d)  Each of the Warrants has been duly and validly authorized by
the Company and constitutes the valid and legally binding agreement of the
Company, enforceable against the Company in accordance with its terms, except
as (i) the enforceability thereof may be limited by bankruptcy, insolvency,
reorganization, fraudulent conveyance, moratorium or other similar laws now or
hereafter in effect relating to rights of creditors and other obligees
generally and (ii) the remedy of specific performance and other forms of
equitable relief may be subject to certain equitable defenses and principles
and to the discretion of the court before which the proceedings may be
brought.

          (e)  The Company is a corporation duly organized and validly
existing in good standing under the laws of the State of Iowa with full
corporate power and authority to own, lease and operate its properties and to
conduct its business as described in the Registration Statement and the
Prospectuses, and is duly registered and qualified to conduct its business and
is in good standing in each jurisdiction where the nature of its properties or
the conduct of its business requires such registration or qualification,
except where the failure so to register or qualify does not have a material
adverse effect on the condition (financial or other), business, properties,
net worth or results of operations of the Company and the Subsidiaries (as
hereinafter defined), taken as a whole (a "Material Adverse Effect").

          (f)     All of the Company's subsidiaries (collectively, the
"Subsidiaries") are listed in Exhibit 21.1 to the Registration Statement. 
Each Subsidiary is a corporation duly organized, validly existing and in good
standing in the jurisdiction of its incorporation, with full corporate power
and authority to own, lease and operate its properties and to conduct its
business as described in the Registration Statement and the Prospectus, and is
duly registered and qualified to conduct its business and is in good standing
in each jurisdiction or place where the nature of its properties or the
conduct of its business requires such registration or qualification, except
where the failure so to register or qualify does not have a Material Adverse
Effect; all the outstanding shares of capital stock of each of the
Subsidiaries have been duly authorized and validly issued, are fully paid and
nonassessable, and, except as set forth in the Prospectus, are owned by the
Company directly, or indirectly through one of the other Subsidiaries, free
and clear of any lien, adverse claim, security interest, equity or other
encumbrance.

                                      14
<PAGE>
 
          (g) There are no legal or governmental proceedings pending or, to
the knowledge of the Company, threatened, against the Company or any of the
Subsidiaries which are materially adverse to the Company and its Subsidiaries,
taken as a whole, or to which the Company or any of the Subsidiaries, or to
which any of their respective properties, is subject which are material to the
Company and its Subsidiaries, taken as a whole, that are required to be
described in the Registration Statement or the Prospectuses but are not
described as required, and there are no agreements, contracts, indentures,
leases, licenses or other instruments or documents relating to the Company or
the Subsidiaries that are required to be described in the Registration
Statement or the Prospectuses or to be filed as an exhibit to the Registration
Statement that are not described or filed as required by the Act.  The
descriptions of the terms of any such agreements, contracts, indentures,
leases, licenses, instruments or documents contained in the Registration
Statement or the Prospectuses are correct in all material respects. 

          (h)  Neither the Company nor any of the Subsidiaries is in (i)
violation of its certificate or articles of incorporation, by-laws, or other
organizational documents, (ii) in violation of any law, ordinance,
administrative or governmental rule or regulation applicable to the Company or
any of the Subsidiaries or of any decree of any court or governmental agency
or body having jurisdiction over the Company or any of the Subsidiaries
(except where any such violation or violations in the aggregate would not have
a Material Adverse Effect), or (iii) in default in the performance of any
obligation, agreement or condition contained in any bond, debenture, note or
any other evidence of indebtedness or in any agreement, indenture, lease or
other instrument to which the Company or any of the Subsidiaries is a party or
by which any of them or any of their respective properties may be bound, and
no condition or state of facts exists, which with the passage of time or the
giving of notice or both, would constitute such a default (except where any
such default or defaults in the aggregate would not have a Material Adverse
Effect). 

          (i)  Neither the issuance and sale of the Shares, the execution,
delivery or performance of this Agreement or the International Underwriting
Agreement by the Company nor the consummation by the Company of the
transactions contemplated hereby and thereby (including, without limitation,
the inclusion in the Registration Statement of the Additional Shares to be
sold by the Selling Shareholders) (i) requires any consent, approval,
authorization or other order of or registration or filing with, any court,
regulatory body, administrative agency or other governmental body, agency or
official (except such as may be required for the registration of the Shares
under the Act and compliance with the securities or Blue Sky laws of various
jurisdictions, all of which have been or will be effected in accordance with
this Agreement), (ii) conflicts or will conflict with or constitutes or will
constitute a breach of, or a default under, the certificate or articles of
incorporation or bylaws, or other organizational

                                      15
<PAGE>
 
documents, of the Company or any of the Subsidiaries or (iii) conflicts or
will conflict with or constitutes or will constitute a breach of, or a default
under, any agreement, indenture, lease, license or other instrument to which
the Company or any of the Subsidiaries is a party or by which any of them or
any of their respective properties may be bound, or violates or will violate
any statute, law, regulation or filing or judgment, injunction, order or
decree applicable to the Company or any of the Subsidiaries or any of their
respective properties, or will result in the creation or imposition of any
lien, charge or encumbrance upon any property or assets of the Company or any
of the Subsidiaries pursuant to the terms of any agreement or instrument to
which any of them is a party or by which any of them may be bound or to which
any of the property or assets of any of them is subject except in the case of
clauses (i) and (iii) where the failure to obtain such consent, approval,
authorization or order, or effect such filing or registration, or such
conflicts, defaults, violations or other action will not have, individually or
in the aggregate, a Material Adverse Effect.

          (j)  The accountants, KPMG Peat Marwick LLP, who have certified or
shall certify the financial statements filed or to be filed as part of the
Registration Statement or the Prospectuses (or any amendment or supplement
thereto) are independent public accountants as required by the Act.

          (k)  The financial statements, together with related schedules and
notes forming part of the Registration Statement and the Prospectuses (and any
amendment or supplement thereto), present fairly the consolidated financial
position, results of operations, cash flows and changes in stockholders'
equity of the Company and the Subsidiaries on the basis stated in the
Registration Statement at the respective dates or for the respective periods
to which they apply; such statements and related schedules and notes have been
prepared in accordance with generally accepted accounting principles
consistently applied throughout the periods involved, except as disclosed
therein; and the other financial and statistical information and data set
forth in the Registration Statement and the Prospectuses (and any amendment or
supplement thereto) are accurately presented in all material respects and
prepared on a basis consistent in all material respects with the books and
records of the Company and its Subsidiaries. 

          (l)  The execution and delivery of, and the performance by the
Company of its obligations under, each of this Agreement and the International
Underwriting Agreement have been duly and validly authorized by the Company,
and each of this Agreement and the International Underwriting Agreement has
been duly executed and delivered by the Company and constitutes the valid and
legally binding agreement of the Company, enforceable against the Company in
accordance with its terms, except (i) the enforceability hereof or thereof may
be limited by bankruptcy, insolvency, reorganization, fraudulent conveyance,
moratorium or other similar

                                    16
<PAGE>
 
laws now or hereafter in effect relating to rights of creditors and other
obligees generally, (ii) the remedy of specific performance and other forms of
equitable relief may be subject to certain equitable defenses and principles
and to the discretion of the court before which the proceedings may be brought
and (iii) rights to indemnity and contribution hereunder or thereunder may be
limited by federal or state securities laws or the public policy underlying
such laws.

          (m)  Except as disclosed in the Registration Statement and the
Prospectuses (or any amendment or supplement thereto), subsequent to the
respective dates as of which such information is given in the Registration
Statement and the Prospectuses (or any amendment or supplement thereto),
neither the Company nor any of the Subsidiaries has incurred any liability or
obligation, direct or contingent, or entered into any transaction, not in the
ordinary course of business, that is material to the Company and the
Subsidiaries taken as a whole, and there has not been any change in the
capital stock of the Company, or material increase in the short-term debt or
long-term debt, of the Company or any of the Subsidiaries, or any development
having or which would reasonably be expected to have, a Material Adverse
Effect. 

          (n)  Each of the Company and the Subsidiaries has good and
marketable title to all property (real and personal) described in the
Prospectuses as being owned by it, free and clear of all liens, claims,
security interests or other encumbrances except such as are described in the
Registration Statement and the Prospectuses or in a document filed as an
exhibit to the Registration Statement, except where the failure to have such
title would not have a Material Adverse Effect and all property described in
the Prospectuses as being held under lease by each of the Company and the
Subsidiaries is held by it under valid, subsisting and enforceable leases
except as enforcement may be limited by applicable bankruptcy, insolvency,
reorganization, fraudulent conveyance, moratorium or other similar laws now or
hereafter in effect relating to rights of creditors and other obligees
generally or by general equitable principles with only such exceptions as in
the aggregate are not materially burdensome and do not interfere in any
material respect with the conduct of the business of the Company and the
Subsidiaries, taken as a whole. 

          (o)  The Company has not distributed and, prior to the later to
occur of (i) the Closing Date or the Option Closing Date, if any, and (ii)
completion of the distribution of the Shares, will not distribute any offering
material in connection with the offering and sale of the Shares other than the
Registration Statement, the Prepricing Prospectuses, the Prospectuses or other
materials, if any, permitted by the Act. 

          (p)  The Company and each of the Subsidiaries have such consents,
approvals, permits, licenses, franchises and authorizations of and from all
United States and foreign, federal,

                                   17
<PAGE>
 
state or provincial, local and other governmental or regulatory authorities
(collectively, the "Licenses") as are necessary to own its respective
properties and to conduct its business in the manner described in the
Prospectuses, except where the failure to have any such License would not have
a Material Adverse Effect and subject to such qualifications as may be set
forth in the Prospectuses; the Company and each of the Subsidiaries has
fulfilled and performed all its material obligations with respect to such
Licenses and no event has occurred that allows, or after notice or lapse of
time or both would allow, revocation or termination thereof or results in any
other material impairment of the rights of the holder of any such License,
except where any of the foregoing would not have individually or in the
aggregate a Material Adverse Effect and subject in each case to such
qualification as may be set forth in the Prospectuses; and, except as
described in the Prospectuses, none of such Licenses contains any restriction
or conditions that is materially burdensome to the Company or any of the
Subsidiaries. Without limiting the generality of this paragraph 7(p): 

               (i)     The Company and each of the Subsidiaries hold all
     telecommunications regulatory licenses, permits, authorizations, consents
     and approvals (the "Telecommunications Licenses") required from the
     Federal Communications Commission (the "FCC") for the Company and the
     Subsidiaries to conduct their business in the manner described in or
     contemplated by the Prospectuses, except as would not have, individually
     or in the aggregate, a Material Adverse Effect; the Telecommunications
     Licenses have been duly and validly issued and are in full force and
     effect, except where the failure to be in full force and effect would not
     have, individually or in the aggregate, a Material Adverse Effect; no
     proceedings to revoke or restrict the Telecommunications Licenses are
     pending or, to the best of our knowledge, threatened; neither the Company
     nor the Subsidiaries are in violation of any of the terms and conditions
     of any of the Telecommunications Licenses, are in violation of the
     Communications Act of 1934, as amended (the "Communications Act"), or are
     in violation of any FCC rules and regulations, except as would not have,
     individually or in the aggregate, a Material Adverse Effect; and the
     Company and the Subsidiaries have in effect with the FCC all
     international and domestic service tariffs necessary to conduct their
     business in the manner described in or contemplated by the Prospectuses
     except as would not have, individually or in the aggregate, a Material
     Adverse Effect;

             (ii)     The Company and the Subsidiaries have obtained all state
     Telecommunications Licenses and filed all tariffs required for the
     provision of telecommunications services in any state to conduct their
     business in the manner described in or contemplated by the Prospectuses,
     except where the failure to do so would not have, individually or in the
     aggregate, a Material Adverse Effect;

                                      18
<PAGE>
 
               (iii)     There is no outstanding adverse judgment, injunction,
     decree or order that has been issued by the FCC or any state public
     utility commission or similar state agency ("PUC") against the Company or
     the Subsidiaries or any action, proceeding or investigation pending
     before the FCC or any state PUC, or, to the best of the Company's
     knowledge, threatened by the FCC or any state PUC against the Company or
     the Subsidiaries which, if the subject of any unfavorable decision,
     ruling or finding, would have a Material Adverse Effect on the Company or
     the Subsidiaries;

              (iv)     No license, permit, consent, approval, order or
     authorization of, or filing with, the FCC or with any state PUC on the
     part of the Company or the Subsidiaries is required in connection with
     the issuance or sale of the Common Stock;

              (v)     Neither the issuance and sale of the Common Stock nor
     the performance by the Company or the Subsidiaries of their obligations
     under the U.S. Underwriting Agreement or the International Underwriting
     Agreement will result in a violation in any material respect of the
     Communications Act or any applicable FCC rules or regulations, or any
     order, writ, judgment, injunction, decree or award of the FCC binding on
     the Company or the Subsidiaries; and

             (vi)     Neither the Company nor the Subsidiaries are in non-
     compliance in the provision of international call-back service with the
     laws of any foreign jurisdiction that would constitute a violation of the
     Telecommunications Licenses, except where such non-compliance would not
     have a Material Adverse Effect and subject to such qualifications as may
     be set forth in the Prospectuses.

           (q)  The Company maintains a system of internal accounting controls
sufficient to provide reasonable assurances that (i) transactions are executed
in accordance with management's general or specific authorization; (ii)
transactions are recorded as necessary to permit preparation of financial
statements in conformity with generally accepted accounting principles and to
maintain accountability for assets; (iii) access to assets is permitted only
in accordance with management's general or specific authorization; and (iv)
the recorded accountability for assets is compared with existing assets at
reasonable intervals and appropriate action is taken with respect to any
differences. 

          (r)  To the Company's knowledge, neither the Company nor any of its
Subsidiaries nor any employee or agent of the Company or any Subsidiary has
made any payment of funds of the Company or any Subsidiary or received or
retained any funds in violation of any law, rule or regulation, which payment,
receipt or retention of funds is of a character required to be disclosed in
the Prospectuses. 

                                      19
<PAGE>
 
          (s)  Except as disclosed in the Prospectuses, the Company and each
of the Subsidiaries have filed all material tax returns required to be filed,
which returns are true and correct in all material respects, and neither the
Company nor any Subsidiary is in default in the payment of any taxes which
were payable pursuant to said returns or any assessments with respect thereto.

          (t)  Except as described in the Prospectuses, no holder of any
security of the Company has any right to require registration of shares of
Common Stock or any other security of the Company because of the filing of the
Registration Statement or consummation of the transactions contemplated by
this Agreement or the International Underwriting Agreement, or otherwise.  No
such rights with respect to shares of Common Stock not listed in Schedule II
hereto were exercised nor will be exercised in connection with the sale of the
Shares and for a period of 180 days after the date hereof.  Except as
described in or contemplated by the Prospectuses, there are no outstanding
options, warrants or other rights calling for the issuance of, and there are
no commitments, plans or arrangements to issue, any shares of Common Stock of
the Company or any security convertible into or exchangeable or exercisable
for Common Stock of the Company. 

          (u)  The Company and the Subsidiaries own or possess all patents,
trademarks, trademark registration, service marks, service mark registrations,
trade names, copyrights, licenses, inventions, trade secrets and rights
described in the Prospectuses as being owned by them or any of them or
necessary for the conduct of their respective businesses except where the lack
of such ownership or possession would not have a Material Adverse Effect, and
the Company is not aware of any claim to the contrary or any challenge by any
other person to the rights of the Company and the Subsidiaries with respect to
the foregoing.

          (v)  The Company is not and, upon sale of the Shares to be issued
and sold in accordance herewith and upon application of the net proceeds to
the Company from such sale as described in the Prospectuses under the caption
"Use of Proceeds," will not be an "investment company" within the meaning of
the Investment Company Act of 1940, as amended.

          (w)  The Company has complied with all provisions of Florida
Statutes, Section 517.075, relating to issuers doing business with Cuba. 

          (x)  The Recapitalization (as defined in the Prospectus) and the
Stock Split (as defined in the Prospectus) will be, prior to or simultaneously
with the consummation of the public offering of the Shares contemplated
hereby, consummated in the manner described in the Prospectus.

                                      20
<PAGE>
 
          (y)  Each of the Company and the Subsidiaries maintains insurance of
the types and in the amounts reasonably adequate for its business, including,
but not limited to, business interruption insurance and insurance covering
real and personal property owned or leased by the Company or such Subsidiary
against theft, damage, destruction, acts of vandalism and all other risks
customarily insured against by corporations of established reputation engaged
in the same or similar businesses and similarly situated, all of which
insurance is in full force and effect.

     8.     Representations and Warranties of the Selling
            Shareholders.

          A.  Each of the Selling Shareholders, other than the Greenwich
Street Affiliates, severally and not jointly, represents and warrants to each
U.S. Underwriter that:

          (a)     Such Selling Shareholder now has, and on the Closing Date
and the Option Closing Date, if any, will have, valid and marketable title to
the Additional Shares to be sold by such Selling Shareholder, free and clear
of any lien, claim, security interest or other encumbrance, including, without
limitation, any restriction on transfer.

          (b)     Such Selling Shareholder now has, and on the Closing Date
and the Option Closing Date, if any, will have, full legal right, power and
authorization, and any approval required by law, to sell, assign, transfer and
deliver such Additional Shares in the manner provided in this Agreement and
the International Underwriting Agreement, and upon delivery of and payment for
such Additional Shares hereunder, the several U.S. Underwriters will acquire
valid and marketable title to such Additional Shares free and clear of any
lien, claim, security interest, or other encumbrance (other than any lien,
claim or security interest placed thereon by the U.S. Underwriters or
Managers). 

          (c)     This Agreement, the International Underwriting Agreement and
the Custody Agreement entered into by such Selling Shareholder, have been duly
authorized, executed and delivered by or on behalf of such Selling Shareholder
and are the valid and binding agreements of such Selling Shareholder
enforceable against such Selling Shareholder in accordance with their terms,
except that (i) the enforceability hereof or thereof may be limited by
bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium or
other similar laws now or hereafter in effect relating to rights of creditors
or other obligees generally, (ii) the remedy of specific performance and other
forms of equitable relief may be subject to certain equitable defenses and
principles and to the discretion of the court before which the proceedings may
be brought and (iii) rights to indemnity and contribution hereunder or
thereunder may be limited by federal or state securities laws or the public
policy underlying such laws. 

                                     21
<PAGE>
 
          (d)     Neither the sale of the Additional Shares, the execution,
delivery or performance of this Agreement, the International Underwriting
Agreement or the Custody Agreement entered into by such Selling Shareholder by
or on behalf of such Selling Shareholder nor the consummation by or on behalf
of such Selling Shareholder of the transactions contemplated hereby and
thereby (i) requires any consent, approval, authorization or other order of,
or registration or filing with, any court, regulatory body, administrative
agency or other governmental body, agency or official (except such as may be
required for the registration of the Shares under the Act and compliance with
the securities or Blue Sky laws of various jurisdictions, all of which have
been or will be effected in accordance with this Agreement) or (ii) conflicts
or will conflict with or constitutes or will constitute a breach of, or a
default under, any agreement, indenture, lease or other instrument to which
such Selling Shareholder is a party or by which such Selling Shareholder is or
may be bound, or violates or will violate any statute, law, regulation or
filing or judgment, injunction, order or decree applicable to such Selling
Shareholder, or will result in the creation or imposition of any lien, charge
or encumbrance upon any property or assets of such Selling Shareholder
pursuant to the terms of any agreement or instrument to which such Selling
Shareholder is a party or by which such Selling Shareholder may be bound or to
which any of the property or assets of such Selling Shareholder is subject
except where the failure to obtain such consent, approval, authorization or
order, or effect such filing or registration, or such conflicts, defaults,
violations or other action will not have, individually or in the aggregate, a
Material Adverse Effect.

          (e)     The information pertaining to such Selling Shareholder under
the caption "Principal and Selling Shareholders" in the Prospectuses, does not
and will not contain an untrue statement of a material fact or omit to state
any material fact required to be stated therein or necessary to make the
statements therein not misleading.

          (f)     The representations and warranties of such Selling
Shareholder in the Custody Agreement entered into by such Selling Shareholder
are, and on the Closing Date and any Option Closing Date will be, true and
correct.

          (g)     Such Selling Shareholder has not taken, directly or
indirectly, any action designed to or that might reasonably be expected to
cause or result in stabilization or manipulation of the price of the Common
Stock to facilitate the sale or resale of the Shares, except for the lock-up
arrangements referred to in the Prospectuses.

          B.  Each Greenwich Street Affiliate represents and warrants to each
U.S. Underwriter that:

                                      22
<PAGE>
 
          (a)     Such Selling Shareholder now has, and on the Closing Date
and the Option Closing Date, if any, will have, valid and marketable title to
the Warrants exercisable for the Additional Shares to be sold by such Selling
Shareholder hereunder, free and clear of any lien, claim, security interest or
other encumbrance, including, without limitation, any restriction on transfer;
and on the Closing Date and the Option Closing Date, if any, such Selling
Shareholder will have, valid and marketable title to the Additional Shares
issuable upon exercise of the Warrants and to be sold by such Selling
Shareholder hereunder, free and clear of any lien, claim, security interest or
other encumbrance, including, without limitation, any restriction on transfer.

          (b)     Such Selling Shareholder now has, and on the Closing Date
and the Option Closing Date, if any, will have, full legal right, power and
authorization, and any approval required by law, to exercise the Warrants for
the Additional Shares and sell, assign, transfer and deliver such Additional
Shares in the manner provided in this Agreement and the International
Underwriting Agreement, and upon delivery of and payment for such Additional
Shares hereunder, the several U.S. Underwriters will acquire valid and
marketable title to such Shares free and clear of any lien, claim, security
interest, or other encumbrance. 

          (c)     This Agreement, the International Underwriting Agreement and
the Greenwich Street Custody Agreement have been duly authorized, executed and
delivered by or on behalf of such Selling Shareholder and are the valid and
binding agreements of such Selling Shareholder enforceable against such
Selling Shareholder in accordance with their terms, except that (i) the
enforceability hereof or thereof may be limited by bankruptcy, insolvency,
reorganization, fraudulent conveyance, moratorium or other similar laws now or
hereafter in effect relating to rights of creditors and other obligees
generally, (ii) the remedy of specific performance and other forms of
equitable relief may be subject to certain equitable defenses and principles
and to the discretion of the court before which the proceedings may be brought
and (iii) rights to indemnity and contribution hereunder or thereunder may be
limited by federal or state securities laws or the public policy underlying
such laws. 

          (d)     None of the exercise of the Warrants for the Additional
Shares to be sold by such Selling Shareholder hereunder, the sale of such
Additional Shares, the execution, delivery or performance of this Agreement,
the International Underwriting Agreement or the Greenwich Street Custody
Agreement by or on behalf of such Selling Shareholder nor the consummation by
or on behalf of such Selling Shareholder of the transactions contemplated
hereby and thereby (i) requires any consent, approval, authorization or other
order of, or registration or filing with, any court, regulatory body,
administrative agency or other governmental body, agency or official (except
such as may be required for the registration of the Shares under the Act or
compliance with the

                                      23
<PAGE>
 
securities or Blue Sky laws of various jurisdictions), or (ii) conflicts or
will conflict with or constitutes or will constitute a breach of, or a default
under, any agreement, indenture, lease or other instrument to which such
Selling Shareholder is a party or by which such Selling Shareholder is or may
be bound, or violates or will violate any statute, law, regulation or filing
or judgment, injunction, order or decree applicable to such Selling
Shareholder, or will result in the creation or imposition of any lien, charge
or encumbrance upon any property or assets of such Selling Shareholder
pursuant to the terms of any agreement or instrument to which such Selling
Shareholder is a party or by which such Selling Shareholder may be bound or to
which any of the property or assets of such Selling Shareholder is subject.

          (e)     The information pertaining to such Selling Shareholder under
the caption "Principal and Selling Shareholders" in the Prospectuses, does not
and will not contain an untrue statement of a material fact or omit to state
any material fact required to be stated therein or necessary to make the
statements therein not misleading. 

          (f)     The representations and warranties of such Selling
Shareholder in the Greenwich Street Custody Agreement are, and on the Closing
Date and the Option Closing Date, if any, will be, true and correct. 

          (g)     Such Selling Shareholder has not taken, directly or
indirectly, any action designed to or that might reasonably be expected to
cause or result in stabilization or manipulation of the price of the Common
Stock to facilitate the sale or resale of the Shares, except for the lock-up
arrangements referred to in the Prospectuses.

     9.     Indemnification and Contribution.  (a) The Company, Fred Gratzon
and Clifford Rees (the "Indemnifying Selling Shareholders"), jointly and
severally, agree to indemnify and hold harmless you and each other U.S.
Underwriter and each person, if any, who controls any U.S. Underwriter within
the meaning of Section 15 of the Act or Section 20(a) of the Exchange Act from
and against any and all losses, claims, damages, liabilities and expenses
(including reasonable costs of investigation) arising out of or based upon any
untrue statement or alleged untrue statement of a material fact contained in
any U.S. Prepricing Prospectus or in the Registration Statement or the U.S.
Prospectus or in any amendment or supplement thereto, or arising out of or
based upon any omission or alleged omission to state therein a material fact
required to be stated therein or necessary to make the statements therein not
misleading, except insofar as such losses, claims, damages, liabilities or
expenses arise out of or are based upon any untrue statement or omission or
alleged untrue statement or omission which has been made therein or omitted
therefrom in reliance upon and in conformity with the information relating to
such U.S. Underwriter or Manager furnished in writing to the

                                     24
<PAGE>
 
Company by or on behalf of any U.S. Underwriter through you or by or on behalf
of any Manager through a Lead Manager expressly for use in connection
therewith; provided, however, that the indemnification contained in this
paragraph (a) with respect to any U.S. Prepricing Prospectus shall not inure
to the benefit of any U.S. Underwriter (or to the benefit of any person
controlling such U.S. Underwriter) on account of any such loss, claim, damage,
liability or expense arising from the sale of the Shares by such U.S.
Underwriter to any person if a copy of the U.S. Prospectus shall not have been
delivered or sent to such person within the time required by the Act and the
regulations thereunder, and the untrue statement or alleged untrue statement
or omission or alleged omission of a material fact contained in such U.S.
Prepricing Prospectus was corrected in the U.S. Prospectus, provided that the
Company has delivered the corrected U.S. Prospectus to the several U.S.
Underwriters in requisite quantity on a timely basis to permit such delivery
or sending.

          (b)  If any action, suit or proceeding shall be brought against any
U.S. Underwriter or any person controlling any U.S. Underwriter in respect of
which indemnity may be sought against the Company or any Indemnifying Selling
Shareholder, such U.S. Underwriter or such controlling person shall promptly
notify the parties against whom indemnification is being sought (the
"indemnifying parties"), and such indemnifying parties shall assume the
defense thereof, including the employment of counsel and payment of all fees
and expenses.  Such U.S. Underwriter or any such controlling person shall have
the right to employ separate counsel in any such action, suit or proceeding
and to participate in the defense thereof, but the fees and expenses of such
counsel shall be at the expense of such U.S. Underwriter or such controlling
person unless (i) the indemnifying parties have agreed in writing to pay such
fees and expenses, (ii) the indemnifying parties have failed to assume the
defense and employ counsel, or (iii) the named parties to any such action,
suit or proceeding (including any impleaded parties) include both such U.S.
Underwriter or such controlling person and the indemnifying parties and such
U.S. Underwriter or such controlling person shall have been advised by its
counsel in writing that representation of such indemnified party and any
indemnifying party by the same counsel would be inappropriate under applicable
standards of professional conduct (whether or not such representation by the
same counsel has been proposed) due to actual or potential differing interests
between them (in which case the indemnifying party shall not have the right to
assume the defense of such action, suit or proceeding on behalf of such U.S.
Underwriter or such controlling person).  It is understood, however, that the
indemnifying parties shall, in connection with any one such action, suit or
proceeding or separate but substantially similar or related actions, suits or
proceedings in the same jurisdiction arising out of the same general
allegations or circumstances, be liable for the reasonable fees and expenses
of only one separate firm of attorneys (in addition to any local counsel) at
any time for all such U.S. Underwriters and

                                      25
<PAGE>
 
controlling persons not having actual or potential differing interests with
you or among themselves, which firm shall be designated in writing by Smith
Barney Inc., and that all such reasonable fees and expenses shall be
reimbursed as they are incurred.  The indemnifying parties shall not be liable
for any settlement of any such action, suit or proceeding effected without
their written consent, but if settled with such written consent, or if there
be a final judgment for the plaintiff in any such action, suit or proceeding,
the indemnifying parties agree to indemnify and hold harmless any U.S.
Underwriter and any such controlling person, to the extent provided in the
preceding paragraph, from and against any loss, claim, damage, liability or
expense by reason of such settlement or judgment. 

          (c)  Each other Selling Shareholder agrees, severally and not
jointly, to indemnify and hold harmless each of you and each other U.S.
Underwriter and each person, if any, who controls any U.S. Underwriter within
the meaning of Section 15 of the Act or Section 20(a) of the Exchange Act, the
Company, its directors, its officers who sign the Registration Statement, and
any person who controls the Company within the meaning of Section 15 of the
Act or Section 20(a) of the Exchange Act to the same extent as the foregoing
indemnity from the Company and the Indemnifying Selling Shareholders to each
U.S. Underwriter, but only with respect to the information furnished in
writing by or on behalf of such Selling Shareholder expressly for use in the
Registration Statement, the U.S. Prospectus or any U.S. Prepricing Prospectus,
or any amendment or supplement thereto.  If any action, suit or proceeding
shall be brought against any U.S. Underwriter, any such controlling person of
any U.S. Underwriter, the Company, any of its directors, any such officer, or
any such controlling person of the Company, based on the Registration
Statement, the U.S. Prospectus or any U.S. Prepricing Prospectus or any
amendment or supplement thereto, and in respect of which indemnity may be
sought against any Selling Shareholder pursuant to this paragraph (c), such
Selling Shareholder shall have the rights and duties given to the Company by
paragraph (b) above (except that if the Company shall have assumed the defense
thereof such Selling Shareholder shall not be required to do so, but may
employ separate counsel therein and participate in the defense thereof, but
the fees and expenses of such counsel shall be at such Selling Shareholder's
expense), and each U.S. Underwriter, each such controlling person of any U.S.
Underwriter, the Company, its directors, any such officer, and any such
controlling person of the Company shall have the rights and duties given to
the U.S. Underwriters by paragraph (b) above.  The foregoing indemnity
agreement shall be in addition to any liability which any Selling Shareholder
may otherwise have.

          (d)     Each U.S. Underwriter agrees, severally and not jointly, to
indemnify and hold harmless the Company, its directors, its officers who sign
the Registration Statement, any person who controls the Company within the
meaning of Section 15 of the Act or Section 20(a) of the Exchange Act and the
Selling Shareholders, to

                                   26
<PAGE>
 
the same extent as the foregoing indemnity from the Company and the
Indemnifying Selling Shareholders to each U.S. Underwriter, but only with
respect to information relating to such U.S. Underwriter furnished in writing
by or on behalf of such U.S. Underwriter through you expressly for use in the
Registration Statement, the U.S. Prospectus or any U.S. Prepricing Prospectus,
or any amendment or supplement thereto.  If any action, suit or proceeding
shall be brought against the Company, any of its directors, any such officer,
any such controlling person or any Selling Shareholder based on the
Registration Statement, the U.S. Prospectus or any U.S. Prepricing Prospectus,
or any amendment or supplement thereto, and in respect of which indemnity may
be sought against any U.S. Underwriter pursuant to this paragraph (d), such
U.S. Underwriter shall have the rights and duties given to the Company and the
Indemnifying Selling Shareholders by paragraph (b) above (except that if the
Company or the Selling Shareholders shall have assumed the defense thereof
such U.S. Underwriter shall not be required to do so, but may employ separate
counsel therein and participate in the defense thereof, but the fees and
expenses of such counsel shall be at such U.S. Underwriter's expense), and the
Company, its directors, any such officer, any such controlling person, and the
Selling Shareholders, shall have the rights and duties given to the U.S.
Underwriters by paragraph (b) above. 

          (e)  If the indemnification provided for in this Section 9 is
unavailable to an indemnified party under paragraphs (a), (c) or (d) hereof in
respect of any losses, claims, damages, liabilities or expenses referred to
therein, then an indemnifying party, in lieu of indemnifying such indemnified
party, shall contribute to the amount paid or payable by such indemnified
party as a result of such losses, claims, damages, liabilities or expenses (i)
in such proportion as is appropriate to reflect the relative benefits received
by the Company and the Selling Shareholders on the one hand and the U.S.
Underwriters on the other hand from the offering of the Shares, or (ii) if the
allocation provided by clause (i) above is not permitted by applicable law, in
such proportion as is appropriate to reflect not only the relative benefits
referred to in clause (i) above but also the relative fault of the Company and
the Selling Shareholders on the one hand and the U.S. Underwriters on the
other hand in connection with the statements or omissions that resulted in
such losses, claims, damages, liabilities or expenses, as well as any other
relevant equitable considerations.  The relative benefits received by the
Company and the Selling Shareholders on the one hand and the U.S. Underwriters
on the other hand shall be deemed to be in the same proportion as the total
net proceeds from the offering (before deducting expenses) received by the
Company and the Selling Shareholders bear to the total underwriting discounts
and commissions received by the U.S. Underwriters, in each case as set forth
in the table on the cover page of the U.S. Prospectus; provided that, in the
event that the U.S. Underwriters shall have purchased any Additional Shares
hereunder, any determination of the relative benefits received by the Company,
the Selling Shareholders

                                      27
<PAGE>
 
or the U.S. Underwriters from the offering of the Shares shall include the net
proceeds (before deducting expenses) received by the Selling Shareholders, and
the underwriting discounts and commissions received by the U.S. Underwriters,
from the sale of such Additional Shares, in each case computed on the basis of
the respective amounts set forth in the notes to the table on the cover page
of the U.S. Prospectus.  The relative fault of the Company and the Selling
Shareholders on the one hand and the U.S. Underwriters on the other hand shall
be determined by reference to, among other things, whether the untrue or
alleged untrue statement of a material fact or the omission or alleged
omission to state a material fact relates to information supplied by the
Company or the Selling Shareholders on the one hand or by the U.S.
Underwriters on the other hand and the parties' relative intent, knowledge,
access to information and opportunity to correct or prevent such statement or
omission. 

          (f)  The Company, the Selling Shareholders and the U.S. Underwriters
agree that it would not be just and equitable if contribution pursuant to this
Section 9 were determined by a pro rata allocation (even if the U.S.
Underwriters were treated as one entity for such purpose) or by any other
method of allocation that does not take account of the equitable
considerations referred to in paragraph (e) above.  The amount paid or payable
by an indemnified party as a result of the losses, claims, damages,
liabilities and expenses referred to in paragraph (e) above shall be deemed to
include, subject to the limitations set forth above, any legal or other
expenses reasonably incurred by such indemnified party in connection with
investigating any claim or defending any such action, suit or proceeding. 
Notwithstanding the provisions of this Section 9, no U.S. Underwriter shall be
required to contribute any amount in excess of the amount by which the total
price of the Shares underwritten by it and distributed to the public exceeds
the amount of any damages which such U.S. Underwriter has otherwise been
required to pay by reason of such untrue or alleged untrue statement or
omission or alleged omission and none of the Greenwich Street Affiliates shall
be required to contribute an amount hereunder with respect to any loss, claim,
damage, liability or expense in excess of the amount such Selling Shareholder
would have been required to pay under Section 9 hereof with respect thereto if
the indemnification provided for in Section 9 had been available with respect
to such loss, claim, damage, liability or expense.  No person guilty of
fraudulent misrepresentation (within the meaning of Section 11(f) of the Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation.  The U.S. Underwriters' obligations to
contribute pursuant to this Section 9 are several in proportion to the
respective numbers of Firm Shares set forth opposite their names in Schedule I
hereto (or such numbers of Firm Shares increased as set forth in Section 12
hereof) and not joint. 

          (g)  No indemnifying party shall, without the prior written consent
of the indemnified party, effect any settlement of

                                      28
<PAGE>
 
any pending or threatened action, suit or proceeding in respect of which any
indemnified party is or could have been a party and indemnity could have been
sought hereunder by such indemnified party, unless such settlement includes an
unconditional release of such indemnified party from all liability on claims
that are the subject matter of such action, suit or proceeding.

          (h)  Any losses, claims, damages, liabilities or expenses for which
an indemnified party is entitled to indemnification or contribution under this
Section 9 shall be paid by the indemnifying party to the indemnified party as
such losses, claims, damages, liabilities or expenses are incurred.  The
indemnity and contribution agreements contained in this Section 9 and the
representations and warranties of the Company and the Selling Shareholders set
forth in this Agreement shall remain operative and in full force and effect,
regardless of (i) any investigation made by or on behalf of any U.S.
Underwriter or any person controlling any U.S. Underwriter, the Company, its
directors or officers or the Selling Shareholders, any director, officer or
partner of a Selling Shareholder or any person controlling the Company or any
Selling Shareholder, (ii) acceptance of any Shares and payment therefor
hereunder, and (iii) any termination of this Agreement.  A successor to any
U.S. Underwriter or any person controlling any U.S. Underwriter, or to the
Company, its directors or officers, or to a Selling Shareholder, any director,
officer or partner of a Selling Shareholder or any person controlling the
Company or any Selling Shareholder, shall be entitled to the benefits of the
indemnity, contribution and reimbursement agreements contained in this Section
9.

     10.  Conditions of U.S. Underwriters' Obligations.  The several
obligations of the U.S. Underwriters to purchase the Firm Shares hereunder are
subject to the following conditions:

          (a)  If, at the time this Agreement is executed and delivered, it is
necessary for the Registration Statement or a post-effective amendment thereto
to be declared effective before the offering of the Shares may commence, the
Registration Statement or such post-effective amendment shall have become
effective not later than 5:30 P.M. New York City time, on the date hereof, or
at such later date and time as shall be consented to in writing by you, and
all filings, if any, required by Rules 424 and 430A under the Act shall have
been timely made; no stop order suspending the effectiveness of the
Registration Statement shall have been issued and no proceeding for that
purpose shall have been instituted or, to the knowledge of the Company or any
U.S. Underwriter, threatened by the Commission, and any request of the
Commission for additional information (to be included in the Registration
Statement or the Prospectuses or otherwise) shall have been complied with to
your reasonable satisfaction. 

          (b)  Subsequent to the effective date of this Agreement, there shall
not have occurred (i) any change, or any development

                                      29
<PAGE>
 
involving a prospective change, that would have a Material Adverse Effect in
or affecting the condition (financial or otherwise), business, prospects,
properties, net worth or results of operations of the Company or the
Subsidiaries not contemplated by the Prospectuses, which in your opinion, as
Representatives of the several U.S. Underwriters, would materially, adversely
affect the market for the Shares, or (ii) any event or development relating to
or involving the Company or any officer or director of the Company or any
Selling Shareholder which makes any statement made in the Prospectuses untrue
in any material respect or which, in the opinion of the Company and its
counsel or the U.S. Underwriters and their counsel, requires the making of any
addition to or change in the Prospectuses in order to state a material fact
required by the Act or any other law to be stated therein or necessary in
order to make the statements therein not misleading, if amending or
supplementing the Prospectuses to reflect such event or development would, in
your opinion, as Representatives of the several U.S. Underwriters, materially
adversely affect the market for the Shares.

          (c)  You shall have received on the Closing Date an opinion of
Swidler & Berlin, Chartered, counsel for the Company, the Gratzons, Clifford
Rees, Steve Rubin and Steve Foster (the "TG Selling Shareholders"), dated the
Closing Date and addressed to you, as Representatives of the several U.S.
Underwriters, to the effect that:

               (i)     The Registration Statement and all post-effective
amendments, if any, have become effective under the Act and, to the knowledge
of such counsel, no stop order suspending the effectiveness of the
Registration Statement has been issued and no proceedings for that purpose are
pending before or contemplated by the Commission; and any required filing of
the Prospectuses pursuant to Rule 424(b) has been made in accordance with Rule
424(b);

               (ii)     Neither the issuance, sale or delivery of the
Underwritten Shares, nor the execution, delivery or performance of the U.S.
Underwriting Agreement or the International Underwriting Agreement, or
compliance by the Company with all provisions of this Agreement and the
International Underwriting Agreement, nor consummation by the Company of the
transactions contemplated hereby or by the International Underwriting
Agreement constitutes or will constitute a breach of, or a default under, the
certificate or articles of incorporation or bylaws of the Company or its
Subsidiaries or any material agreement, indenture, lease or other instrument
to which the Company or any Subsidiary is a party or by which they or any of
their properties is bound and that is made an exhibit to the Registration
Statement, or, except as disclosed in the Registration Statement, will result
in the creation or imposition of any lien, charge or encumbrance upon any
property or assets of the Company or any Subsidiary under any such agreement,
indenture, lease or other instrument, which breach default or other

                                      30
<PAGE>
 
event would have a Material Adverse Effect, nor will any such action result in
any violation of any existing law, regulation, ruling (assuming compliance
with all applicable state securities and Blue Sky laws), judgment, injunction,
order or decree known to such counsel after reasonable inquiry, to be
applicable to the Company, any Subsidiary or any of their properties, which
violation would have a Material Adverse Effect;

               (iii)     No consent, approval, authorization or other order,
or registration or filing with, any court, regulatory body, administrative
agency or other governmental body, agency, or official is required on the part
of the Company (except as have been obtained under the Act or such as may be
required under state securities or Blue Sky laws governing the purchase and
distribution of the Shares) for the valid issuance and sale of the Shares to
the U.S. Underwriters as contemplated by the U.S. Underwriting Agreement;

               (iv)     The Registration Statement and the Prospectuses and
any supplements or amendments thereto (except for the financial statements,
schedules, and notes thereto and other financial and statistical data included
therein or omitted therefrom, as to which such counsel need not express any
opinion) comply as to form in all material respects with the requirements of
the Act;

               (v)     To the knowledge of such counsel, (A) other than as
described in the Prospectuses, there are no legal or governmental proceedings
pending or threatened against the Company or any Subsidiary or to which the
Company's or any Subsidiary's properties are subject, which, if adversely
determined, would reasonably be expected to have a Material Adverse Effect,
and (B) there are no agreements, contracts, indentures, leases or other
instruments relating to the Company or any Subsidiary, of a character that are
required to be described in the Registration Statement or the Prospectuses or
to be filed as an exhibit to the Registration Statement that are not described
or filed as required, as the case may be;

               (vi)     The U.S. Underwriting Agreement, the International
Underwriting Agreement and the Custody Agreements have each been duly executed
and delivered by or on behalf of each of the TG Selling Shareholders and are
valid and binding agreements of each TG Selling Shareholder enforceable
against each TG Selling Shareholder in accordance with their respective terms
except that (i) enforceability may be limited by bankruptcy, insolvency,
reorganization, fraudulent conveyances, moratorium or other similar laws now
or hereafter in effect relating to rights of creditors and other obligees
generally, (ii) the remedy of specific performance and other forms of
equitable relief may be subject to certain equitable defenses and principles
and to the discretion of the court before which the proceedings may be brought
and (iii) rights to indemnity and contribution thereunder may be limited by
Federal or state securities laws or the public policy underlying such laws;

                                      31
<PAGE>
 
               (vii)     Each TG Selling Shareholder has full legal right,
power and authority, and any approval required by law, to sell, assign,
transfer and deliver good and marketable title to the Additional Shares which
such TG Selling Shareholder has agreed to sell pursuant to the U.S.
Underwriting Agreement and the International Underwriting Agreement;

               (viii)    The execution and delivery of the U.S. Underwriting
Agreement, the International Underwriting Agreement and the Custody Agreement
by the TG Selling Shareholders and the consummation of the transactions
contemplated thereby will not conflict with, constitute a breach of, or a
default under any material agreement, indenture, lease or other instrument
known to such counsel to which any TG Selling Shareholder is a party or by
which any of them or any of their assets or property is bound, or violate any
statute, law, regulation, court order or decree known to such counsel to be
applicable to any TG Selling Shareholder or to any of the property or assets
of any TG Selling Shareholder, except for any such conflicts, breaches,
defaults or violations that would not have a Material Adverse Effect on the
ability of such TG Selling Shareholder to consummate the transactions
contemplated by the Underwriting Agreements;

               (ix)     (A) Each TG Selling Shareholder has full right power,
and authority to enter into this Agreement, the International Underwriting
Agreement, the respective Powers of Attorneys and the Custody Agreements, and
(B) upon delivery of the Additional Shares to be sold by such TG Selling
Shareholder hereunder and payment of the purchase price therefor as herein
contemplated, each of the U.S. Underwriters will receive good and marketable
title to its ratable share of the Additional Shares purchased by it from such
TG Selling Shareholder, free and clear of any pledge, lien, security interest,
encumbrance, claim or equity, assuming the U.S. Underwriters acquire the
Additional Shares without notice of any adverse claim as such term is used in
Section 8-302 of the Uniform Commercial Code in effect in the State of New
York;

               (x)     The Section 214 Switched Voice Authorization, the
Section 214 Private Line Authorization, and the Section 214 Facilities
Authorization (as such terms are defined in the Prospectus) are the only
telecommunications regulatory licenses, permits, authorizations, consents and
approvals ("Telecommunications Licenses") required from the Federal
Communications Commission (the "FCC") for each of the Company and the
Subsidiaries to conduct its business in the manner described in the
Prospectus.  The FCC Telecommunications Licenses currently held by each of the
Company and the Subsidiaries have been duly and validly issued and are in full
force and effect, and no proceedings to revoke or restrict such FCC
Telecommunications Licenses are pending or, to our knowledge, threatened. 
Each of the Company and the Subsidiaries is not in violation of any of

                                      32
<PAGE>
 
the terms and conditions of any of its FCC Telecommunications Licenses, is not
in violation of the Communications Act of 1934, as amended, and is not in
violation of any FCC rules and regulations, except to the extent that such
violation is disclosed in the Registration Statement and would not have a
Material Adverse Effect.  Each of the Company and the Subsidiaries has in
effect with the FCC all international switched, international private line
and/or United States domestic interexchange service tariffs necessary to
conduct its business in the manner described in the Prospectus;

               (xi)     To the extent they constitute a summary of legal
matters, documents or proceedings referred to therein, the statements in the
Prospectus under the captions "Risk Factors - Substantial Government
Regulation-United States" and "Business-Government Regulation" are accurate in
all material respects and fairly summarize in all material respects all
matters referred to therein, and there are no material omissions under such
captions with respect to such legal matters, documents and proceedings;

               (xii)    Each of the Company and the Subsidiaries has obtained
all state Telecommunications Licenses and filed all tariffs required for the
provision of telecommunications services in any state to conduct its business
in the manner described in or contemplated by the Prospectus except where the
failure to obtain such licenses and/or file such tariffs would not have,
individually or in the aggregate, a Material Adverse Effect;

               (xiii)   There is no outstanding adverse judgment,
injunction, decree or order that has been issued by the FCC against the
Company or any Subsidiary or any action, proceeding or investigation pending
before the FCC or, to such counsel's knowledge, threatened by the FCC against
the Company or any Subsidiary or otherwise which, if the subject of an
unfavorable decision, ruling or finding, would have a Material Adverse Effect;

               (xiv)    There is no outstanding adverse judgment, injunction,
decree or order that has been issued by any state public utility commission
("PUC") against the Company or any Subsidiary or any action, proceeding or
investigation pending before or, to counsel's knowledge, threatened by any
state PUC against the Company or any Subsidiary which, if the subject of an
unfavorable decision, ruling or finding, would have a Material Adverse Effect;

               (xv)     No license, permit, consent, approval, order or
authorization of, or filing with, the FCC or with any state PUC on the part of
the Company or any Subsidiary is required in connection with the issuance or
sale of the Common Stock;

               (xvi)    Neither the issuance and sale of the Common Stock nor
the performance by the Company of its obligations under

                                     33
<PAGE>
 
the U.S. Underwriting Agreement or the International Underwriting Agreement
will result in a violation of the Communications Act, or any applicable rules
or the regulations promulgated under the Communications Act, or, to counsel's
knowledge, any order, writ, judgment, injunction, decree or award of the FCC
binding on the Company or any Subsidiary; and

               (xvii)   The Section 214 Switched Voice Authorization, the
Section 214 Private Line Authorization and the Section 214 Facilities
Authorization require the Company and its Subsidiaries to provide any
international call-back service using uncompleted call signaling in a manner
that is consistent with the laws of the countries in which they operate.
Although we do not provide legal services to the Company or its Subsidiaries
regarding the application or interpretation of any non-U.S. law and although we
have performed no due diligence in this regard other than discussing with
management of the Company the Company's operations and compliance with
applicable FCC requirements and reviewing any portions of the opinions of local
counsel of Australia, France, Germany, Hong Kong, Japan, the Netherlands,
Sweden, Switzerland, and the United Kingdom specifically regarding the provision
of international call-back service in certain jurisdictions in which the Company
operates, we are not aware of any non-compliance in the provision of
international call-back service by the Company with the laws of any of these
foreign jurisdictions in which the Company operates that would constitute a
violation of the Section 214 Switched Voice Authorization, the Section 214
Private Line Authorization, or the Section 214 Facilities Authorization and have
a Material Adverse Effect on the Company and its Subsidiaries, taken as a whole,
except as described in the Prospectuses under the captions "Risk Factors --
Substantial Government Regulation" and "Business -- Government Regulation
Overview." For the purpose of making this statement, we have relied upon our
discussions with management of the Company and our review of any portions of the
opinions of local counsel of Australia, France, Germany, Hong Kong, Japan, the
Netherlands, Sweden, Switzerland, and the United Kingdom specifically regarding
the provision of international call-back service provided by the Company,
without any further inquiry or any independent review of any laws of any such
jurisdictions.

          In addition, such counsel shall state that although counsel has not
undertaken, except as otherwise indicated in their opinion, to determine
independently, and does not assume any responsibility for, the accuracy,
completeness or fairness of the statements in the Registration Statement, such
counsel has participated in the preparation of the Registration Statement and
the Prospectuses, including general review and discussion of the contents
thereof but has made no independent check or verification thereof (relying as
to materiality to a large extent upon the opinions of officers and other
representatives of the Company), and no facts have come to the attention of
such counsel that would lead them to believe that the Registration Statement
at the time the Registration Statement became effective, or the Prospectuses,
as of

                                      34
<PAGE>
 
their respective dates and as of the Closing Date or the Option Closing Date,
as the case may be, contained an untrue statement of a material fact or
omitted to state a material fact required to be stated in the Prospectuses or
necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading or that any amendment or supplement
to the Prospectuses, as of its respective date, and as of the Closing Date or
the Option Closing Date, as the case may be, contained any untrue statement of
a material fact or omitted to state a material fact required to be stated in
the Prospectuses or necessary in order to make the statements in the
Prospectuses, in the light of the circumstances under which they were made,
not misleading (it being understood that such counsel need express no
statement with respect to the financial statements, schedules, pro forma
financial statements and the notes thereto and other financial and statistical
data included in or omitted from the Registration Statement or the
Prospectuses).

          In rendering their opinion as aforesaid, counsel may, as to factual
matters, rely upon written certificates or statements of officers of the
Company and the Selling Shareholders and, as to matters of law, may rely upon
an opinion or opinions, each dated the Closing Date, of other counsel retained
by them or the Company as to laws of any jurisdiction other than the United
States, the State of Delaware or the State of New York provided that (1) each
such local counsel is reasonably acceptable to the Representatives, (2) such
reliance is expressly authorized by each opinion so relied upon and a copy of
each such opinion is delivered to the Representatives and is, in form and
substance reasonably satisfactory to them and their counsel, and (3) counsel
shall state in their opinion that they believe that they and the U.S.
Underwriters are justified in relying thereon.

          (d)  You shall have received on the Closing Date an opinion of
Debevoise & Plimpton, counsel for the Greenwich Street Affiliates, dated the
Closing Date and addressed to you, as Representatives of the several U.S.
Underwriters, to the effect that:

               (i)     The U.S. Underwriting Agreement, the International
Underwriting Agreement and the Greenwich Street Custody Agreement have each
been duly executed and delivered by or on behalf of each of the Greenwich
Street Affiliates and are valid and binding agreements of each of the
Greenwich Street Affiliates enforceable against each Greenwich Street
Affiliate in accordance with their respective terms except that (i)
enforceability may be limited by bankruptcy, insolvency, reorganization,
fraudulent conveyances, moratorium or other similar laws now or hereafter in
effect relating to rights of creditors and other obligees generally, (ii) the
remedy of specific performance and other forms of equitable relief may be
subject to certain equitable defenses and principles and to the discretion of
the court before which the proceedings may be brought and (iii) rights to
indemnity and

                                      35
<PAGE>
 
contribution thereunder may be limited by Federal or state securities laws or
the public policy underlying such laws;

               (ii)     Each Greenwich Street Affiliate has full legal right,
power and authority, and any approval required by law, to exercise the
Warrants for the Additional Shares to be sold by it, and to sell, assign,
transfer and deliver good and marketable title to the Additional Shares which
such Affiliate has agreed to sell pursuant to the U.S. Underwriting Agreement
and the International Underwriting Agreement;

               (iii)     The execution and delivery of the U.S. Underwriting
Agreement, the International Underwriting Agreement and the Greenwich Street
Custody Agreement by the Greenwich Street Affiliates and the consummation of
the transactions contemplated thereby will not conflict with, constitute a
breach of, or a default under any material agreement, indenture, lease or
other instrument known to such counsel to which any Greenwich Street Affiliate
is a party or by which any of them or any of their assets or property is
bound, or violate any statute, law, regulation, court order or decree known to
such counsel to be applicable to any Greenwich Street Affiliate or to any of
the property or assets of any Greenwich Street Affiliate, except for any such
conflicts, breaches, defaults or violations that would not have a Material
Adverse Effect on the ability of such Greenwich Street Affiliate to consummate
the transactions contemplated by the Underwriting Agreements;

               (iv)     (A) Each Greenwich Street Affiliate has full right
power, and authority to enter into this Agreement, the International
Underwriting Agreement and the Greenwich Street Custody Agreement, and (B)
upon delivery of the Additional Shares to be sold by such Greenwich Street
Affiliate hereunder and payment of the purchase price therefor as herein
contemplated, each of the U.S. Underwriters will receive good and marketable
title to its ratable share of the Additional Shares purchased by it from such
Greenwich Street Affiliate, free and clear of any pledge, lien, security
interest, encumbrance, claim or equity, assuming the U.S. Underwriters acquire
the Additional Shares without notice of any adverse claim as such term is used
in Section 8-302 of the Uniform Commercial Code in effect in the State of New
York;

          In rendering their opinion as aforesaid, counsel may, as to factual
matters, rely upon written certificates or statements of officers of the
Company and the Selling Shareholders and, as to matters of law, may rely upon
an opinion or opinions, each dated the Closing Date, of other counsel retained
by them or the Company as to laws of any jurisdiction other than the United
States, the State of Delaware or the State of New York provided that (1) each
such local counsel is reasonably acceptable to the Representatives, (2) such
reliance is expressly authorized by each opinion so relied upon and a copy of
each such opinion is delivered to the

                                      36
<PAGE>
 
Representatives and is, in form and substance reasonably satisfactory to them
and their counsel, and (3) counsel shall state in their opinion that they
believe that they and the U.S. Underwriters are justified in relying thereon.

          (e)  You shall have received on the Closing Date an opinion of
Marcus & Thompson, special counsel for the Company and the TG Selling
Shareholders in connection with matters relating to Iowa law, dated the
Closing Date and addressed to you, as Representatives of the several U.S.
Underwriters, to the effect that:

               (i)     The Company is a corporation duly incorporated and
validly existing in good standing under the laws of the State of Iowa with full
corporate power and authority to own, lease and operate its properties and to
conduct its business as described in the Registration Statement and the
Prospectuses, and is duly qualified and in good standing in all other
jurisdictions in which the nature of the business transacted or property owned
or leased by it makes such qualification necessary, except where the failure so
to qualify or be in good standing would not have, individually or in the
aggregate, a Material Adverse Effect on the Company and its Subsidiaries taken
as a whole;

               (ii)     (A)  The Company has the corporate power and authority
to enter into the U.S. Underwriting Agreement and the International
Underwriting Agreement and to issue, sell and deliver the Shares to be sold by
it to the U.S. Underwriters and Managers as provided therein, and (B) each of
the U.S. Underwriting Agreement and the International Underwriting Agreement
have been duly authorized, executed and delivered by the Company and is a
legal, valid and binding agreement of the Company, enforceable against the
Company in accordance with its terms, except that (1) enforceability may be
limited by bankruptcy, insolvency, reorganization, fraudulent conveyance,
moratorium or other similar laws now or hereafter in effect relating to rights
of creditors and other obligees generally, (2) the remedy of specific
performance and other forms of equitable relief may be subject to certain
equitable defenses and principles and to the discretion of the court before
which the proceedings may be brought and (3) rights to indemnity and
contribution thereunder may be limited by Federal or state securities laws or
the public policy underlying such laws;

               (iii)     The authorized capital stock of the Company is as set
forth under the caption "Capitalization" in the Prospectuses; and the
authorized capital stock of the Company conforms in all material respects as
to legal matters to the description thereof contained in the Prospectuses
under the caption "Description of Capital Stock";

               (iv)     All the shares of capital stock of the Company
outstanding prior to the issuance of the Shares to be issued and sold by the
Company pursuant to the U.S. Underwriting Agreement and

                                      37
<PAGE>
 
the International Underwriting Agreement (including the Shares to be sold by
the Gratzons, Clifford Rees, Steve Rubin and Steve Foster) have been duly
authorized and validly issued, are fully paid, nonassessable and free of
preemptive or similar rights;

               (v)     Each of the Warrants has been duly and validly authorized
by the Company and constitutes the valid and legally binding agreement of the
Company, enforceable against the Company in accordance with its terms, except as
(i) the enforceability thereof may be limited by bankruptcy, insolvency,
reorganization, moratorium or other similar laws now or hereafter in effect
relating to rights of creditors and other obligees generally and (ii) the remedy
of specific performance and other forms of equitable relief may be subject to
certain equitable defenses and principles and to the discretion of the court
before which the proceedings may be brought.

               (vi)     The Shares to be issued and sold to the U.S.
Underwriters and Managers by the Company under the U.S. Underwriting Agreement
and the International Underwriting Agreement have been duly authorized and
when issued and delivered to the U.S. Underwriters and Managers against
payment therefor in accordance with the terms of the U.S. Underwriting
Agreement and the International Underwriting Agreement, will be (A) duly
authorized and validly issued, fully paid and nonassessable and (B) free of
any preemptive or similar rights; and

               (vii)     The Additional Shares and the Additional
International Shares to be issued and sold to the U.S. Underwriters and
Managers by the Greenwich Street Affiliates under the U.S. Underwriting
Agreement and the International Underwriting Agreement have duly authorized
for issuance upon exercise of the Warrants and, when issued and delivered to
the Greenwich Street Affiliates by the Company upon exercise of the Warrants
against payment of the exercise price therefor, will be validly issued, fully
paid and non-assessable and free of any preemptive or similar rights.

               (viii)     The form of certificates for the Shares conforms to
the requirements of the Business Corporation Act of the State of Iowa.

          (f)  You shall have received on the Closing Date opinions of Baker &
McKenzie (Australia) in the form attached hereto as exhibit   , Baker &
McKenzie (Hong Kong) in the form attached hereto as exhibit   , Baker &
McKenzie (Germany) in the form attached hereto as exhibit   , Coudert Freres
(France) in the form attached hereto as exhibit   , TMI Associates (Japan) in
the form attached hereto as exhibit   , Stibbe Simont Monahan Duhot (The
Netherlands) in the form attached hereto as exhibit   ,[            ] (United
Kingdom) in the form attached hereto as exhibit   , [         ] (Sweden) in
the form attached hereto as exhibit   and [          ] (Switzerland) in the
form attached hereto as exhibit   , special regulatory counsel for the Company
in

                                      38
<PAGE>
 
each of the jurisdictions described above, each dated the Closing Date and
addressed to you, as Representatives of the several U.S. Underwriters, to the
effect that, with respect to each such jurisdiction:

          (g)  You shall have received on the Closing Date an opinion from
Charles Johanson, Esq., Corporate Counsel for the Company, dated the Closing
Date and addressed to you, as Representatives of the several U.S.
Underwriters, to the effect that:

               (i)     Each of the Subsidiaries is a corporation duly
organized, validly existing and in good standing in the jurisdiction of its
incorporation, with full corporate power and authority to own, lease, and
operate its properties and to conduct its business as described in the
Registration Statement and the Prospectuses; and all the outstanding shares of
capital stock of each of the Subsidiaries that is a corporation have been duly
authorized and validly issued, are fully paid and nonassessable, and, except
for director's qualifying shares and as otherwise disclosed in the
Prospectuses, are owned by the Company directly, or indirectly through one of
the other Subsidiaries, free and clear of any lien, adverse claim, security
interest, equity or other encumbrance; and

               (ii)     None of the Company or its Subsidiaries is (A) in
violation of its certificate or articles of incorporation or bylaws, or other
organizational documents or (B) to the best knowledge of such counsel after
reasonable inquiry, in default in any material respect in the performance of
any material obligation, agreement or condition contained in any bond,
debenture, note or other evidence of indebtedness, except as may be disclosed
in the Prospectuses or where any such default or defaults in the aggregate
would not have a Material Adverse Effect.

          In addition, the Company's Corporate Counsel shall state that
although Counsel has not undertaken, except as otherwise indicated in its
opinion, to determine independently, and does not assume any responsibility
for, the accuracy, completeness or fairness of the statements in the
Registration Statement, such counsel has participated in the preparation of
the Registration Statement and the Prospectuses, including general review and
discussion of the contents thereof but has made no independent check or
verification thereof (relying as to materiality to a large extent upon the
opinions of officers and other representatives of the Company), and no facts
have come to the attention of such Counsel that would lead him to believe that
the Registration Statement at the time the Registration Statement became
effective, or the Prospectuses, as of their respective dates and as of the
Closing Date or the Option Closing Date, as the case may be, contained an
untrue statement of a material fact or omitted to state a material fact
required to be stated in the Prospectuses or necessary to make the statements
therein, in the light of the circumstances under which they were made, not
misleading or that any amendment or supplement to the Prospectuses, as of its
respective date, and as of the Closing Date or the Option Closing Date, as the
case may be, contained any untrue statement of a material fact or omitted to
state a material fact required to be stated in the Prospectuses or necessary
in order to make the statements in the Prospectuses, in the light of the

                                      39
<PAGE>
 
circumstances under which they were made, not misleading (it being understood
that the Company's Corporate Counsel need express no statement with respect to
the financial statements, schedules, pro forma financial statements and the
notes thereto and other financial and statistical data included in or omitted
from the Registration Statement or the Prospectuses).

             In rendering such opinion as aforesaid, the Company's Corporate
Counsel may, as to factual matters, rely upon written certificates or
statements of officers of the Company and the Subsidiaries and, as to matters
of law, may rely upon an opinion or opinions, each dated the Closing Date, of
other counsel retained by him or the Company as to laws of any jurisdiction
other than the United States or the State of Iowa provided that (1) each such
local counsel is reasonably acceptable to the Representatives, (2) such
reliance is expressly authorized by each opinion so relied upon and a copy of
each such opinion is delivered to the Representatives and is, in form and
substance reasonably satisfactory to them and their counsel, and (3) Charles
Johanson shall state in his opinion that he believes that they and the U.S.
Underwriters are justified in relying thereon.

          (h)  You shall have received on the Closing Date an opinion of
Chadbourne & Parke LLP, counsel for the U.S. Underwriters, dated the Closing
Date, with respect to the matters referred to in clauses (c)(i), (c)(iv),
(c)(ix)(B), the paragraph immediately following clause (xvii) of the foregoing
paragraph (c) and (d)(iv)(B) and such other related matters as you may
request.

          (i)  You shall have received letters addressed to you, as
Representatives of the several U.S. Underwriters, and dated the date hereof
and the Closing Date from KPMG Peat Marwick LLP, independent certified public
accountants, substantially in the forms heretofore approved by you. 

          (j)  (1) No stop order suspending the effectiveness of the
Registration Statement shall have been issued and no proceedings for that
purpose shall have been taken or, to the knowledge of the Company, shall be
contemplated by the Commission at or prior to the Closing Date; (2) there
shall not have been any material change in the capital stock of the Company
nor any material increase in the short-term or long-term debt of the Company
(other than in the ordinary course of business) from that set forth or
contemplated in the Registration Statement or the Prospectuses (or any
amendment or supplement thereto); (3) there shall not have been, since the
respective dates as of which

                                      40
<PAGE>
 
information is given in the Registration Statement and the Prospectuses (or
any amendment or Supplement thereto), except as may otherwise be stated in the
Registration Statement and Prospectuses (or any amendment or supplement
thereto), any material adverse change in the condition (financial or other),
business, prospects, properties, net worth or results of operations of the
Company and the Subsidiaries taken as a whole; and (4) all the representations
and warranties of the Company contained in this Agreement shall be true and
correct on and as of the date hereof and on and as of the Closing Date as if
made on and as of the Closing Date, and you shall have received a certificate,
dated the Closing Date and signed by the chief executive officer and the chief
financial officer of the Company (or such other officers as are acceptable to
you), to the effect set forth in this Section 10(j) and in Section 10(k)
hereof. 

          (k)  The Company shall not have failed at or prior to the Closing
Date to have performed or complied with any of its agreements herein contained
and required to be performed or complied with by it hereunder at or prior to
the Closing Date. 

          (l)  All the representations and warranties of the Selling
Shareholders contained in this Agreement shall be true and correct, on and as
of the date hereof and on and as of the Closing Date as if made on and as of
the Closing Date, and you shall have received a certificate, dated the Closing
Date and signed by or on behalf of the Selling Shareholders to the effect set
forth in this Section 10(l) and in Section 10(m) hereof. 

          (m)  The Selling Shareholders shall not have failed at or prior to
the Closing Date to have performed or complied with any of their agreements
contained in this Agreement or the International Underwriting Agreement and
required to be performed or complied with by them at or prior to the Closing
Date.

          (n)  The Sellers shall have furnished or caused to be furnished to
you such further certificates and documents as you shall have reasonably
requested. 

          (o)  The Common Stock shall have been listed or approved for listing
subject to notice of issuance, on the Nasdaq National Market.

          (p)  The closing under the International Underwriting Agreement
shall have occurred or shall be occurring concurrently with the closing
hereunder on the Closing Date.

          All such opinions, certificates, letters and other documents will be
in compliance with the provisions hereof only if they are reasonably
satisfactory in form and substance to you and your counsel. 

                                      41
<PAGE>
 
          Any certificate or document signed by any officer of the Company or
any Attorney-in-Fact or any Selling Shareholder and delivered to you, as
Representatives of the U.S. Underwriters, or to counsel for the U.S.
Underwriters, shall be deemed a representation and warranty by the Company,
the Selling Shareholders or the particular Selling Shareholder, as the case
may be, to each U.S. Underwriter as to the statements made therein. 

          The several obligations of the U.S. Underwriters to purchase
Additional Shares hereunder are subject to the satisfaction on and as of the
Option Closing Date, if any, of the conditions set forth in this Section 10,
except that, if any Option Closing Date is other than the Closing Date, the
certificates, opinions and letters referred to in this Section 10 shall be
dated the Option Closing Date in question and the opinions or letters called
for by paragraphs (c), (d), (e), (f), (g),(h) and (i) shall be revised to
reflect the sale of Additional Shares. 

     11.     Expenses.  The Company agrees to pay the following costs and
expenses and all other costs and expenses incident to the performance by them
of their obligations hereunder:  (i) the preparation, printing or
reproduction, and filing with the Commission of the registration statement
(including financial statements and exhibits thereto), each Prepricing
Prospectus, the Prospectus, and each amendment or supplement to any of them;
(ii) the printing (or reproduction) and delivery (including postage, air
freight (or reproduction) and delivery (including postage, air freight charges
and charges for counting and packaging) of such copies of the registration
statement, each Prepricing Prospectus, the Prospectus, and all amendments or
supplements to any of them as may be reasonably requested for use in
connection with the offering and sale of the Shares; (iii) the preparation,
printing, authentication, issuance and delivery of certificates for the
Shares, including any stamp taxes in connection with the original issuance and
sale of the Shares; (iv) the printing (or reproduction) and delivery of this
Agreement, the Blue Sky Memorandum and all other agreements or documents
printed (or reproduced) and delivered in connection with the offering of the
Shares; (v) the registration of the Common Stock under the Exchange Act and
the listing of the Shares on the Nasdaq National Market; (vi) the registration
or qualification of the Shares for offer and sale under the securities or Blue
Sky laws of the several states as provided in Section 5(g) hereof (including
the reasonable fees, expenses and disbursements of counsel for the
Underwriters relating to the preparation, printing or reproduction, and
delivery of the Blue Sky Memorandum and such registration and qualification,
if any, up to $      .); (vii) the filing fees and the fees and expenses of
counsel for the Underwriters in connection with any filings required to be
made with the National Association of Securities Dealers, Inc. including the
fees and expenses of any qualified independent underwriter; (viii) the
transportation and other expenses incurred by or on behalf of representatives
of the Company in connection with presentations to prospective purchasers

                                   42
<PAGE>
 
of the Shares; and (ix) the fees and expenses of the Company's accountants and
the fees and expenses of counsel (including local and special counsel) for the
Company and the Selling Shareholders.

     12.     Effective Date of Agreement.  This Agreement shall become
effective: (i) upon the execution and delivery hereof by the parties hereto;
or (ii) if, at the time this Agreement is executed and delivered, it is
necessary for the registration statement or a post-effective amendment thereto
to be declared effective before the offering of the Shares may commence, when
notification of the effectiveness of the registration statement or such
post-effective amendment has been released by the Commission.  Until such time
as this Agreement shall have become effective, it may be terminated by the
Company, by notifying you, or by you, as Representatives of the several U.S.
Underwriters, by notifying the Company and the Selling Shareholders. 

          If any one or more of the U.S. Underwriters shall fail or refuse to
purchase Shares which it or they are obligated to purchase hereunder on the
Closing Date, and the aggregate number of Shares which such defaulting U.S.
Underwriter or Underwriters are obligated but fail or refuse to purchase is
not more than one-tenth of the aggregate number of Shares which the U.S.
Underwriters are obligated to purchase on the Closing Date, each
non-defaulting U.S. Underwriter shall be obligated, severally, in the
proportion which the number of Firm Shares set forth opposite its name in
Schedule I hereto bears to the aggregate number of Firm Shares set forth
opposite the names of all non-defaulting U.S. Underwriters or in such other
proportion as you may specify in accordance with Section 20 of the Master
Agreement Among Underwriters of Smith Barney Inc., to purchase the Shares
which such defaulting U.S. Underwriter or Underwriters are obligated, but fail
or refuse, to purchase.  If any one or more of the U.S. Underwriters shall
fail or refuse to purchase Shares which it or they are obligated to purchase
on the Closing Date and the aggregate number of Shares with respect to which
such default occurs is more than one-tenth of the aggregate number of Shares
which the U.S. Underwriters are obligated to purchase on the Closing Date and
arrangements satisfactory to you and the Company for the purchase of such
Shares by one or more non-defaulting U.S. Underwriters or other party or
parties approved by you and the Company are not made within 36 hours after
such default, this Agreement will terminate without liability on the part of
any non-defaulting U.S. Underwriter or the Company.  In any such case which
does not result in termination of this Agreement, either you or the Company
shall have the right to postpone the Closing Date, but in no event for longer
than seven days, in order that the required changes, if any, in the
Registration Statement and the Prospectus or any other documents or
arrangements may be effected.  Any action taken under this paragraph shall not
relieve any defaulting U.S. Underwriter from liability in respect of any such
default of any such U.S. Underwriter under this Agreement.  The term "U.S.
Underwriter" as used in this Agreement includes, for all purposes of this
Agreement, any party not listed in Schedule I

                                      43
<PAGE>
 
hereto who, with your approval and the approval of the Company, purchases
Shares which a defaulting U.S. Underwriter is obligated, but fails or refuses,
to purchase.

          Any notice under this Section 12 may be given by telegram, telecopy
or telephone but shall be subsequently confirmed by letter. 

     13.     Termination of Agreement.  This Agreement shall be subject to
termination in your absolute discretion, without liability on the part of any
U.S. Underwriter to the Company or any Selling Shareholder, by notice to the
Company, if prior to the Closing Date or the Option Closing Date, if any, (if
different from the Closing Date and then only as to the Additional Shares), as
the case may be, (i) trading in securities generally on the New York Stock
Exchange, the American Stock Exchange or the Nasdaq National Market shall have
been suspended or materially limited, (ii) a general moratorium on commercial
banking activities in New York shall have been declared by either federal or
state authorities, or (iii) there shall have occurred any outbreak or
escalation of hostilities or other international or domestic calamity, crisis
or change in political, financial or economic conditions, the effect of which
on the financial markets of the United States is such as to make it, in your
judgment, impracticable or inadvisable to commence or continue the offering of
the Shares at the offering price to the public set forth on the cover page of
the U.S. Prospectus or to enforce contracts for the resale of the Shares by
the U.S. Underwriters.

          Notice of such termination may be given by telegram, telecopy or
telephone and shall be subsequently confirmed by letter. 

     14.     Information Furnished by the U.S. Underwriters.  The statements
set forth in the last paragraph on the cover page, the stabilization legend on
the inside front cover page, and the statements in the first, second, fourth,
seventh, eighth, ninth, tenth, eleventh (as it relates to the Managers),
fourteenth and seventeenth paragraphs under the caption "Underwriting" in any
U.S. Prepricing Prospectus and in the U.S. Prospectus constitute the only
information furnished by or on behalf of the U.S. Underwriters through you as
such information is referred to in Sections 7(b) and 9 hereof.  

     15.     Miscellaneous.  Except as otherwise provided in Sections 5, 12
and 13 hereof, notice given pursuant to any provision of this Agreement shall
be in writing and shall be delivered (i) if to the Company, Fred Gratzon or
Clifford Rees at the office of the Company at, 2098 Nutmeg Avenue, Fairfield,
Iowa 52556, Attention: Fred Gratzon, Chairman; (ii) if to the Greenwich Street
Affiliates, to Stephen R. Hertz at Debevoise & Plimpton, 875 Third Avenue New
York, New York 10022; or (iii) if to you, as Representatives of the several
U.S. Underwriters, care of Smith Barney Inc., 388 Greenwich

                                      44
<PAGE>
 
Street, New York, New York 10013, Attention: Manager, Investment Banking
Division.

          This Agreement has been and is made solely for the benefit of the
several U.S. Underwriters, the Selling Shareholders, the Company, its
directors and officers, the other controlling persons referred to in Section 9
hereof and the Selling Shareholders and their respective successors and
assigns, to the extent provided herein, and no other person shall acquire or
have any right under or by virtue of this Agreement.  Neither the term
"successor" nor the term "successors and assigns" as used in this Agreement
shall include a purchaser from any U.S. Underwriter of any of the Shares in
his status as such purchaser. 

     16.     Applicable Law; Counterparts.  This Agreement shall be governed
by and construed in accordance with the laws of the State of New York
applicable to contracts made and to be performed within the State of New York.

          This Agreement may be signed in various counterparts which together
constitute one and the same instrument.  If signed in counterparts, this
Agreement shall not become effective unless at least one counterpart hereof
shall have been executed and delivered on behalf of each party hereto.

                                      45
<PAGE>
 
          Please confirm that the foregoing correctly sets forth the agreement
among the Company, the Selling Shareholders and the several U.S. Underwriters. 

                                   Very truly yours,

                                   TELEGROUP, INC.

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------
     
                                   FRED GRATZON

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   SHELLEY L. LEVIN-GRATZON

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   CLIFFORD S. REES

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   STEVEN RUBIN

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                      46
<PAGE>
 
                                   STEVEN FOSTER

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   GREENWICH STREET CAPITAL
                                     PARTNERS, L.P.

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   GREENWICH STREET CAPITAL
                                     OFFSHORE FUND, LTD.

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   TRV EMPLOYEES FUND, L.P.

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   THE TRAVELERS INSURANCE COMPANY

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                   THE TRAVELERS LIFE AND
                                     ANNUITY COMPANY

                                   By:                               
                                      -------------------------
                                      Name:
                                           --------------------
                                      Title:
                                            -------------------

                                      47
<PAGE>
 
Confirmed as of the date first
above mentioned on behalf of
themselves and the other several U.S.
Underwriters named in Schedule I
hereto. 

SMITH BARNEY INC.
Alex. Brown & Sons Incorporated
COWEN & COMPANY

As Representatives of the Several U.S. Underwriters

By: SMITH BARNEY INC.


By:                                     
    ---------------------------------
     Managing Director










                                      48
<PAGE>
 
                                  SCHEDULE I


                                Telegroup, Inc.


 
                              Number of                        Number of
Underwriter                   Firm Shares     Underwriter     Firm Shares
------------                  -------------   -----------     -------------
Smith Barney Inc. ...
Alex. Brown & Sons
  Incorporated
Cowen & Company




                                                                -------------
                                                          Total          
                                                                -------------
                                      49
<PAGE>
 
                                  SCHEDULE II


                                Telegroup, Inc.

                                                                Number of
Selling Shareholders                                        Additional Shares
---------------------                                       ------------------

Mr. Fred Gratzon and Shelley L.
  Levin-Gratzon, as joint tenants
Mr. Clifford S. Rees
Mr. Steven Rubin
Mr. Steven Foster
Greenwich Street Capital Partners, L.P.
Greenwich Street Capital Offshore Fund, Ltd.
TRV Employees Fund, L.P.
The Travelers Insurance Company
The Travelers Life and Annuity Company


                                                            -----------------
                                                       Total                   
                                                             ----------------- 
                                      50