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                                                                    EXHIBIT 10.1

                                                                  EXECUTION COPY





                                  $300,000,000

                           IMPSAT FIBER NETWORKS, INC.

                          13 3/4% SENIOR NOTES DUE 2005

                               PLACEMENT AGREEMENT





February 11, 2000

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                                                          February 11, 2000


Morgan Stanley & Co. Incorporated
1585 Broadway
New York, New York  10036

Ladies and Gentlemen:

              IMPSAT Fiber Networks, Inc., a Delaware corporation (the
"Company"), proposes to issue and sell to Morgan Stanley & Co. Incorporated (the
"Placement Agent") $300,000,000 principal amount of its 13 3/4% Senior Notes due
2005 (the "Notes") to be issued pursuant to the provisions of an Indenture to be
dated as of February 16, 2000 (the "Indenture") among the Company, The Bank of
New York, as Trustee, Registrar and Paying Agent and Banque International a
Luxembourg S.A., as Paying Agent and Transfer Agent.

              The Notes will be offered without being registered under the
Securities Act of 1933, as amended (the "Securities Act"), to qualified
institutional buyers (as defined in Rule 144A under the Securities Act) in
compliance with the exemption from registration provided by Rule 144A under the
Securities Act ("Rule 144A").

              In connection with the sale of the Notes, the Company has prepared
a preliminary offering memorandum (the "Preliminary Memorandum") and will
prepare a final offering memorandum (the "Final Memorandum" and, with the
Preliminary Memorandum, each a "Memorandum") setting forth or including a
description of the terms of the Notes, the terms of the offering and a
description of the Company and its business.

              The purchasers of the Notes and their direct and indirect
transferees will be entitled to the benefits of a Registration Rights Agreement
(the "Registration Rights Agreement") dated the date hereof (as defined below).

              1.     Representations and Warranties. The Company represents and
warrants to, and agrees with, you that as of the date hereof:

              (a)    The Preliminary Memorandum does not contain and the Final
       Memorandum, in the form used by the Placement Agent to confirm sales and
       on the Closing Date, will not contain any untrue statement of a material
       fact or omit to state a material fact necessary to make the statements
       therein, in the light of the circumstances under which they were made,
       not misleading, except that the representations and warranties set forth
       in this Section 1(a) do not apply to statements or omissions in either
       Memorandum based upon information relating to the Placement Agent
       furnished to the Company in writing by the Placement Agent expressly for
       use therein.


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              (b)    The Company has been duly incorporated, is validly existing
       as a corporation in good standing under the laws of the State of
       Delaware, United States of America, has the corporate power and authority
       to own its property and to conduct its business as described in each
       Memorandum and is duly qualified to transact business and is in good
       standing in each jurisdiction in which the conduct of its business or its
       ownership or leasing of property requires such qualification, except to
       the extent that the failure to be so qualified or be in good standing
       would not have a material adverse effect on the Company and its
       subsidiaries, taken as a whole. All of the shares of capital stock of the
       Company's subsidiaries owned by the Company have been duly and validly
       authorized and issued, are fully paid and non-assessable and are directly
       owned by the Company, free and clear of all liens, encumbrances, equities
       or claims.

              (c)    Each subsidiary of the Company has been duly incorporated
       and is validly existing under the laws of the jurisdiction of its
       incorporation, has the corporate power and authority to own its property
       and to conduct its business as described in each Memorandum and is duly
       qualified to transact business in each jurisdiction in which the conduct
       of its business or its ownership or leasing of property requires such
       qualification, except to the extent that the failure to be so qualified
       would not have a material adverse effect on such subsidiary. IMPSAT S.A.
       ("IMPSAT Argentina") is a wholly owned subsidiary of the Company, IMPSAT
       S.A. ("IMPSAT Colombia") is a wholly owned subsidiary of the Company,
       Impsatel del Ecuador S.A. ("IMPSAT Ecuador") is a wholly owned subsidiary
       of the Company, IMPSAT S.A. de C.V. ("IMPSAT Mexico") is a 99.9% owned
       subsidiary of the Company, Telecomunicaciones IMPSAT S.A. ("IMPSAT
       Venezuela") is a wholly owned subsidiary of the Company and IMPSAT
       Comunicacoes Ltda. ("IMPSAT Brazil") is a 99.9% owned subsidiary of the
       Company.

              (d)    This Agreement has been duly authorized, executed and
       delivered by the Company.

              (e)    The Registration Rights Agreement has been duly authorized
       and, when executed and delivered by the Company, will be a valid and
       binding agreement of the Company enforceable in accordance with its
       terms, except as (x) the enforceability thereof may be limited by
       bankruptcy, insolvency or similar laws affecting creditors' rights
       generally, (y) the availability of equitable remedies may be limited by
       equitable principles of general applicability and (z) any rights to
       indemnity and contribution may be limited by federal and state securities
       laws and public policy considerations.

              (f)    The Notes have been duly authorized and, when executed,
       authenticated and delivered in accordance with the terms of the Indenture
       and paid for by the Placement Agent in accordance with the terms of this
       Agreement, will (x) be valid and binding obligations of the Company
       enforceable in accordance with their terms, except as (A) the
       enforceability thereof may be limited by bankruptcy, insolvency or
       similar laws


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       affecting creditors' rights generally and (B) rights of acceleration, if
       applicable, and the availability of equitable remedies may be limited by
       equitable principles of general applicability and (y) be entitled to the
       benefits of the Indenture and the Registration Rights Agreement.

              (g)    The Indenture has been duly authorized, executed and
       delivered by the Company, and is a valid and binding agreement of the
       Company, enforceable in accordance with its terms except as (x) the
       enforceability thereof may be limited by bankruptcy, insolvency or
       similar laws affecting creditors' rights generally and (y) rights of
       acceleration, if applicable, and the availability of equitable remedies
       may be limited by equitable principles of general applicability.

              (h)    The execution and delivery by the Company of, and the
       performance by the Company of its obligations under, this Agreement, the
       Indenture, the Registration Rights Agreement, the Notes and the issuance,
       sale and delivery of the Notes will not contravene any provision of
       applicable law or the certificate of incorporation or bylaws of the
       Company, as amended to date, or any agreement or other instrument binding
       upon the Company or any of its subsidiaries or any judgment, order or
       decree of any governmental body, agency or court having jurisdiction over
       the Company or any subsidiary of the Company, and no consent, approval,
       authorization or order of, or qualification with, any governmental body
       or agency is required for the performance by the Company of its
       obligations under this Agreement, the Indenture, the Registration Rights
       Agreement or the Notes or the issuance, sale and delivery of the Notes,
       except (x) for any consents, approvals, authorizations, orders or
       qualifications, the failure to obtain which would not have a material
       adverse effect on the ability of the Company to perform its obligations
       under this Agreement and (y) such as may be required by the securities or
       Blue Sky laws of the various states in connection with the offer and sale
       of the Notes.

              (i)    There has not occurred any material adverse change, or any
       development involving a prospective material adverse change, in the
       condition, financial or otherwise, or in the earnings, business or
       operations of the Company and its subsidiaries, taken as a whole, from
       that set forth in the Preliminary Memorandum.

              (j)    There are no legal or governmental proceedings pending or
       threatened to which the Company or any of its subsidiaries is a party or
       to which any of the properties of the Company or any of its subsidiaries
       is subject other than proceedings accurately described in all material
       respects in each Memorandum and proceedings that would not have a
       material adverse effect on the Company and its subsidiaries, taken as a
       whole, or on the power or ability of the Company to perform its
       obligations under this Agreement, the Indenture, the Registration Rights
       Agreement or the Notes, to consummate the transactions contemplated by
       each such agreement, or to apply the net proceeds of the


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       issuance of the Notes as described in the Final Memorandum under the
       caption "Use of Proceeds."

              (k)    Each of the Company and its subsidiaries has all necessary
       certificates, orders, permits, licenses, authorizations, consents and
       approvals of and from, and has made all declarations and filings with,
       all federal, state, local, foreign supranational, national, regional and
       other governmental authorities and all courts and tribunals, to own,
       lease, license and use its properties and assets and to conduct its
       business in the manner described in the Final Memorandum, and neither the
       Company nor any of its subsidiaries has received any notice of
       proceedings relating to revocation or modification of any such
       certificates, orders, permits, licenses, authorizations, consents or
       approvals, nor is the Company or any of its subsidiaries in violation of,
       or in default under, any federal, state, local, foreign supranational,
       national or regional law, regulation, rule, decree, order or judgment
       applicable to the Company or any of its subsidiaries the effect of which,
       singly or in the aggregate, would have a material adverse effect on the
       Company and its subsidiaries, taken as a whole, except as described in
       the Final Memorandum.

              (l)    Neither the Company nor any affiliate (as defined in Rule
       501(b) of Regulation D under the Securities Act, an "Affiliate") of the
       Company has directly, or through any agent, (i) sold, offered for sale,
       solicited offers to buy or otherwise negotiated in respect of, any
       security (as defined in the Securities Act) which is or will be
       integrated with the sale of the Notes in a manner that would require the
       registration under the Securities Act of the Notes or (ii) engaged in any
       form of general solicitation or general advertising in connection with
       the offering of the Notes (as those terms are used in Regulation D under
       the Securities Act) or in any manner involving a public offering within
       the meaning of Section 4(2) of the Securities Act; provided, however,
       that no such representation or warranty is given or made with respect to
       the Placement Agent or any of its Affiliates.

              (m)    The Company is not, and after giving effect to the offering
       and sale of the Notes and the application of the proceeds thereof as
       described in the Final Memorandum under the caption "Use of Proceeds",
       will not be an "investment company" as such term is defined in the
       Investment Company Act of 1940, as amended.

              (n)    It is not necessary in connection with the offer, sale and
       delivery of the Notes to the Placement Agent in the manner contemplated
       by this Agreement to register the Notes under the Securities Act or to
       qualify the Indenture under the Trust Indenture Act of 1939, as amended.

              (o)    The Company and its subsidiaries (i) are in compliance with
       any and all applicable foreign, federal, state and local laws and
       regulations relating to the protection of human health and safety, the
       environment or hazardous or toxic substances or wastes, pollutants or
       contaminants ("Environmental Laws"), (ii) have received all permits,
       licenses or other approvals required of them under applicable
       Environmental Laws to


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       conduct their respective businesses and (iii) are in compliance with all
       terms and conditions of any such permit, license or approval, except
       where such noncompliance with Environmental Laws, failure to receive
       required permits, licenses or other approvals or failure to comply with
       the terms and conditions of such permits, licenses or approvals would
       not, singly or in the aggregate, have a material adverse effect on the
       Company and its subsidiaries, taken as a whole.

              (p)    There are no costs or liabilities associated with
       Environmental Laws (including, without limitation, any capital or
       operating expenditures required for clean-up, closure of properties or
       compliance with Environmental Laws or any permit, license or approval,
       any related constraints on operating activities and any potential
       liabilities to third parties) which would, singly or in the aggregate,
       have a material adverse effect on the Company and its subsidiaries, taken
       as a whole.

              (q)    None of the Company, its Affiliates or any person acting on
       its or their behalf has engaged in any directed selling efforts (as that
       term is defined in Regulation S under the Securities Act ("Regulation
       S")) with respect to the Notes; provided, however, that no such
       representation or warranty is given or made with respect to the Placement
       Agent or any of its Affiliates.

              (r)    The Company has reviewed its operations and that of its
       subsidiaries to evaluate the extent to which the business or operations
       of the Company or any of its subsidiaries have been or will be affected
       by the Year 2000 Problem (that is, any significant risk that computer
       hardware or software applications used by the Company and its
       subsidiaries during the time periods occurring after December 31, 1999,
       function at least as effectively as in the case of dates or time periods
       occurring prior to January 1, 2000); as a result of such review, nothing
       has come to the attention of the Company as of the date hereof, after due
       inquiry, that any Year 2000 Problems have occurred that (A) could have a
       material adverse effect on the condition, financial or otherwise, or on
       the earnings, business or operations of the Company and its subsidiaries,
       taken as a whole, or result in any material loss or interference with the
       business or operations of the Company and its subsidiaries, taken as a
       whole or (B) are of a character required to be described or referred to
       in the Final Memorandum which have not been accurately described in the
       Final Memorandum.

              (s)    Subsequent to the respective dates as of which information
       is given in the Final Memorandum, (1) the Company and its subsidiaries
       have not incurred any material liability or obligation, direct or
       contingent, nor entered into any material transaction not in the ordinary
       course of business; (2) the Company has not purchased any of its
       outstanding capital stock, nor declared, paid or otherwise made any
       dividend or distribution of any kind on its capital stock other than
       ordinary and customary dividends; and (3) there has not been any material
       change in the capital stock, short-term debt or


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       long-term debt of the Company and its consolidated subsidiaries, except
       in each case as described in the Final Memorandum.

              (t)    The Company and its subsidiaries have good and marketable
       title in fee simple to all real property and good and marketable title to
       all personal property owned by them which is material to the business of
       the Company and its subsidiaries, in each case free and clear of all
       liens, encumbrances and defects except such as are described in the Final
       Memorandum or such as do not materially affect the value of such property
       and do not materially interfere with the use made and proposed to be made
       of such property by the Company and its subsidiaries; and any real
       property and buildings held under lease by the Company and its
       subsidiaries are held by them under valid, subsisting and enforceable
       leases with such exceptions as are not material and do not materially
       interfere with the use made and proposed to be made of such property and
       buildings by the Company and its subsidiaries, in each case except as
       described in the Final Memorandum.

              (u)    The Company and its subsidiaries own or possess, or can
       acquire on reasonable terms, all material patents, patent rights,
       licenses, inventions, copyrights, know-how (including trade secrets and
       other unpatented and/or unpatentable proprietary or confidential
       information, systems or procedures), trademarks, service marks and trade
       names currently employed by them in connection with the business now
       operated by them, and, except as described in the Final Memorandum,
       neither the Company nor any of its subsidiaries has received any notice
       of infringement of or conflict with asserted rights of others with
       respect to any of the foregoing which, singly or in the aggregate, if the
       subject of an unfavorable decision, ruling or finding, would have a
       material adverse effect on the Company and its subsidiaries, taken as a
       whole.

              (v)    No material labor dispute with the employees of the Company
       or any of its subsidiaries exists, except as described in or contemplated
       by the Final Memorandum, or, to the knowledge of the Company, is
       imminent; and the Company is not aware of any existing, threatened or
       imminent labor disturbance by the employees of any of its principal
       suppliers, manufacturers or contractors that could have a material
       adverse effect on the Company and its subsidiaries, taken as a whole.

              (w)    The Company and each of its subsidiaries are insured by
       insurers of recognized financial responsibility against such losses and
       risks and in such amounts as the Company reasonably believes are prudent
       and customary in the businesses in which they are engaged; neither the
       Company nor any such subsidiary has been refused any insurance coverage
       sought or applied for; and neither the Company nor any such subsidiary
       has any reason to believe that it will not be able to renew its existing
       insurance coverage as and when such coverage expires or to obtain similar
       coverage from similar insurers as may be necessary to continue its
       business at a cost that would not have a


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       material adverse effect on the Company and its subsidiaries, taken as a
       whole, except as described in the Final Memorandum.

              (x)    The Company and each of its subsidiaries keep accurate
       books and records reflecting their assets and maintain a system of
       internal accounting controls sufficient to provide reasonable assurance
       that (1) transactions are executed in accordance with management's
       general or specific authorizations; (2) transactions are recorded as
       necessary to permit preparation of consolidated financial statements in
       conformity with generally accepted accounting principles and to maintain
       asset accountability; (3) access to assets is permitted only in
       accordance with management's general or specific authorization; and (4)
       the recorded accountability for assets is compared with the existing
       assets at reasonable intervals and appropriate action is taken with
       respect to any differences.

              (y)    The Notes satisfy the requirements set forth in Rule
       144A(d)(3) under the Securities Act.

              2.     Agreements to Sell and Purchase. The Company hereby agrees
to sell to the Placement Agent, and the Placement Agent, upon the basis of the
representations and warranties herein contained, but subject to the conditions
hereinafter stated, agrees to purchase from the Company $300,000,000 principal
amount of Notes at a purchase price of 98.125% of the principal amount of the
Notes plus accrued interest, if any, to the Closing Date (the "Purchase Price").

              The Company hereby agrees that, without the prior written consent
of Morgan Stanley & Co. Incorporated, as Placement Agent, it will not, during
the period beginning on the date hereof and continuing to and including the
Closing Date, offer, sell, contract to sell or otherwise dispose of any debt of
the Company or warrants to purchase debt of the Company substantially similar to
the Notes (other than the sale of the Notes under this Agreement).

              3.     Terms of Offering. You have advised the Company that the
Placement Agent will make an offering of the Notes purchased by the Placement
Agent hereunder on the terms to be set forth in the Final Memorandum, as soon as
practicable after this Agreement is entered into as in your judgment is
advisable.

              4.     Payment and Delivery. Payment for the Notes shall be made
to the account of the Company in Federal or other funds immediately available in
New York City against delivery of such Notes for the account of the Placement
Agent at 10:00 a.m., New York city time, on February 16, 2000, or at such other
time on the same or such other date, not later than February 28, 2000, as shall
be designated in writing by you. The time and date of such payment are
hereinafter referred to as the "Closing Date."

              Certificates for the Notes shall be in definitive form or global
form, as specified by you, and registered in such names and in such
denominations as you shall request in writing


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not later than one full business day prior to the Closing Date. The certificates
evidencing the Notes shall be delivered to you on the Closing Date for the
account of the Placement Agent, with any transfer taxes payable in connection
with the transfer of the Notes to the Placement Agent duly paid, against payment
of the Purchase Price therefor.

              5.     Conditions to the Placement Agent's Obligations. The
obligation of the Placement Agent under this Agreement to purchase the Notes
will be subject to the following conditions:

              (a)    Subsequent to the date of this Agreement and prior to the
       Closing Date,

                     (i)    there shall not have occurred any downgrading, nor
              shall any notice have been given of any intended or potential
              downgrading or of any review for a possible change that does not
              indicate the direction of the possible change, in the rating
              accorded any of the Company's securities by any "nationally
              recognized statistical rating organization," as such term is
              defined for purposes of Rule 436(g)(2) under the Securities Act;
              and

                     (ii)   there shall not have occurred any change, or any
              development involving a prospective change, in the condition,
              financial or otherwise, or in the earnings, business or
              operations, of the Company and its subsidiaries, taken as a whole,
              from that set forth in the Final Memorandum (exclusive of any
              amendments or supplements thereto subsequent to the date of this
              Agreement) that, in the judgment of Morgan Stanley & Co.
              Incorporated, is material and adverse and that makes it, in the
              judgment of Morgan Stanley & Co. Incorporated, impracticable to
              market the Notes on the terms and in the manner contemplated in
              the Final Memorandum.

              (b)    You shall have received on the Closing Date a certificate,
       dated the Closing Date and signed by an executive officer of the Company,
       to the effect set forth in Section 5(a)(i) above and to the effect that
       the representations and warranties of the Company contained in this
       Agreement are true and correct as of the Closing Date and that the
       Company has complied with all of the agreements and satisfied all of the
       conditions on its part to be performed or satisfied hereunder on or
       before the Closing Date.

              The officer signing and delivering such certificate may rely upon
       the best of his or her knowledge as to proceedings threatened.

              (c)    The Placement Agent shall have received on the Closing Date
       an opinion of Arnold & Porter, special U.S. counsel for the Company,
       dated the Closing Date, to the effect set forth in Exhibit A.


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              (d)    The Placement Agent shall have received on the Closing Date
       an opinion of Nicholson & Cano, Argentine counsel for the Company and
       IMPSAT Argentina, dated the Closing Date, to the effect set forth in
       Exhibit B.

              (e)    The Placement Agent shall have received on the Closing Date
       an opinion of S.E. Consultores Asociados Ltda., Colombian counsel for
       IMPSAT Colombia, dated the Closing Date, to the effect set forth in
       Exhibit C.

              (f)    The Placement Agent shall have received on the Closing Date
       an opinion of Perez Bustamante & Perez, Ecuadoran counsel for IMPSAT
       Ecuador, dated the Closing Date, to the effect set forth in Exhibit D.

              (g)    The Placement Agent shall have received on the Closing Date
       an opinion of Basham, Ringe & Correa, Mexican counsel for IMPSAT Mexico,
       dated the Closing Date, to the effect set forth in Exhibit E.

              (h)    The Placement Agent shall have received on the Closing Date
       an opinion of Baumeister & Brewer, Venezuelan counsel for IMPSAT
       Venezuela, dated the Closing Date, to the effect set forth in Exhibit F.

              (i)    The Placement Agent shall have received on the Closing Date
       an opinion of Pinheiro Neto, Brazilian counsel for IMPSAT Brazil, dated
       the Closing Date, to the effect set forth in Exhibit G.

              (j)    The Placement Agent shall have received on the Closing Date
       an opinion of Latham & Watkins, United States regulatory counsel for the
       Company, dated the Closing Date, to the effect set forth in Exhibit H.

              Each of the opinions referred to in clauses (c) through (j) shall
       be rendered to the Placement Agent at the request of the Company and
       shall so state therein.

              (k)    The Placement Agent shall have received on the Closing Date
       an opinion of Shearman & Sterling, United States counsel for the
       Placement Agent, dated the Closing Date, with respect to such matters as
       you may reasonably request.

              (l)    The Placement Agent shall have received, on each of the
       date hereof and the Closing Date, a letter dated the date hereof or the
       Closing Date, as the case may be, in form and substance satisfactory to
       the Placement Agent, from Deloitte & Touche LLP, independent public
       accountants for the Company, containing statements and information of the
       type ordinarily included in accountants' "comfort letters" to
       underwriters with respect to the financial statements and certain
       financial information contained in the Final Memorandum; provided that
       the letter delivered on the Closing Date shall use a "cut-off date" not
       earlier than the date hereof.


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              (m)    You shall have received such other documents and
       certificates as are reasonably requested by you and your counsel.

              6.     Covenants of the Company. In further consideration of the
agreements of the Placement Agent contained in this Agreement, the Company
covenants with the Placement Agent as follows:

              (a)    To furnish to you in New York City, without charge, prior
       to 10:00 a.m. New York City time on the business day next succeeding the
       date of this Agreement and during the period mentioned in Section 6(c)
       below, as many copies of the Final Memorandum and any supplements and
       amendments thereto as you may reasonably request.

              (b)    Before amending or supplementing either Memorandum, to
       furnish to you a copy of each such proposed amendment or supplement and
       not to use any such proposed amendment or supplement to which you
       reasonably object.

              (c)    If, during such period after the date hereof and prior to
       the date on which all of the Notes shall have been sold by the Placement
       Agent, any event shall occur or condition exist as a result of which it
       is necessary in your judgment to amend or supplement the Final Memorandum
       in order to make the statements therein, in the light of the
       circumstances when such Memorandum is delivered to a purchaser, not
       misleading, or if, in the opinion of United States counsel to the
       Placement Agent it is necessary to amend or supplement such Memorandum to
       comply with applicable law, forthwith to prepare and furnish, at its own
       expense, to the Placement Agent, either amendments or supplements to such
       Memorandum so that the statements in such Memorandum as so amended or
       supplemented will not, in the light of the circumstances when such
       Memorandum is delivered to a purchaser, be misleading or so that such
       Memorandum, as so amended or supplemented, will comply with applicable
       law.

              (d)    To endeavor to qualify the Notes for offer and sale under
       the securities or Blue Sky laws of such jurisdictions as you shall
       reasonably request.

              (e)    Whether or not any sale of the Notes is consummated, to pay
       all expenses incident to the performance of its obligations under this
       Agreement, including: (i) the preparation of each Memorandum and all
       amendments and supplements thereto, (ii) the preparation, issuance and
       delivery of the Notes, (iii) the fees and disbursements of the Company's
       counsel and accountants and the Trustee and its counsel, (iv) the
       qualification of such Notes under securities or Blue Sky laws in
       accordance with the provisions of Section 5(d), including filing fees and
       the fees and disbursements of counsel for the Placement Agent in
       connection therewith and in connection with the preparation of any Blue
       Sky or legal investment memoranda, (v) the printing and delivery to the
       Placement


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       Agent in quantities as hereinabove stated of copies of the Memorandum and
       any amendments or supplements thereto, (vi) any fees charged by rating
       agencies for the rating of the Notes, (vii) all document production
       charges and expenses of counsel to the Placement Agent (but not including
       their fees for professional services) in connection with the preparation
       of this Agreement, (viii) the fees and expenses, if any, incurred in
       connection with the admission of the Notes for trading in any appropriate
       market system and (ix) any expenses incurred by the Company in connection
       with a "road show" presentation to potential investors.

              (f)    Neither the Company nor any Affiliate will sell, offer for
       sale or solicit offers to buy or otherwise negotiate in respect of any
       security (as defined in the Securities Act) which could be integrated
       with the sale of the Notes in a manner which would require the
       registration under the Securities Act of the Notes.

              (g)    Not to solicit any offer to buy or offer or sell the Notes
       by means of any form of general solicitation or general advertising (as
       those terms are used in Regulation D under the Securities Act) or in any
       manner involving a public offering within the meaning of Section 4(2) of
       the Securities Act.

              (h)    While any of the Notes remain outstanding, to make
       available, upon request, to any seller of such Notes the information
       specified in Rule 144A(d)(4) under the Securities Act, unless the Company
       is then subject to Section 13 or 15(d) of the Exchange Act.

              (i)    To use its best efforts to permit the Notes to be
       designated PORTAL securities in accordance with the rules and regulations
       adopted by the National Association of Securities Dealers, Inc. relating
       to trading in the PORTAL Market.

              (j)    None of the Company, its Affiliates or any person acting on
       its or their behalf (other than the Placement Agent) will engage in any
       directed selling efforts (as that term is defined in Regulation S) with
       respect to the Notes, and the Company and its Affiliates and each person
       acting on its or their behalf (other than the Placement Agent) will not
       engage in any selling efforts pursuant to Regulation S.

              (k)    For the sole benefit of the Placement Agent:

              (1)    prior to the consummation of the Exchange Offer (as defined
       in the Registration Rights Agreement) or the effectiveness of a Shelf
       Registration Statement if, in the reasonable judgment of the Placement
       Agent, the Placement Agent or any of its affiliates (as such term is
       defined in the rules and regulations under the Securities Act) is
       required to deliver an offering memorandum in connection with sales of,
       or market-making activities with respect to, the Notes or the Exchange
       Securities (as defined in the Registration Rights Agreement), (A) to
       periodically amend or supplement the Final


<PAGE>   13

                                       12


       Memorandum so that the information contained in the Final Memorandum
       complies with the requirements of Rule 144A of the Securities Act, (B) to
       amend or supplement the Final Memorandum when necessary to reflect any
       material changes in the information provided therein so that the Final
       Memorandum will not contain any untrue statement of a material fact or
       omit to state any material fact necessary in order to make the statements
       therein, in light of the circumstances existing as of the date the Final
       Memorandum is so delivered, not misleading and (C) to provide the
       Placement Agent with copies of each such amended or supplemental Final
       Memorandum, as the Placement Agent may reasonably request;

              (2)    following the consummation of the Exchange Offer or the
       effectiveness of a Shelf Registration Statement and for so long as the
       Notes or, the Exchange Securities are outstanding if, in the reasonable
       judgment of the Placement Agent, the Placement Agent or any of its
       affiliates (as such term is defined in the rules and regulations under
       the Securities Act) is required to deliver a prospectus in connection
       with sales of, or market-making activities with respect to the Notes or
       the Exchange Securities, (A) to periodically amend the applicable
       registration statement so that the information contained therein complies
       with the requirements of Section 10(a) of the Securities Act, (B) if
       requested by the Placement Agent, within 45 days following the end of the
       Company's most recent fiscal quarter, file a supplement to the prospectus
       included in the applicable registration statement which sets forth the
       financial results of the Company for the previous quarter, (C) to amend
       the applicable registration statement or supplement the related
       prospectus or the documents incorporated therein when necessary to
       reflect any material changes in the information provided therein so that
       the registration statement and the prospectus will not contain any untrue
       statement of a material fact or omit to state any material fact necessary
       in order to make the statements therein, in light of the circumstances
       existing as of the date the prospectus is so delivered, not misleading
       and (D) to provide the Placement Agent with copies of each such amendment
       or supplement as the Placement Agent may reasonably request;

              (3)    notwithstanding clauses (1) and (2) above, (A) prior to
       amending the Final Memorandum or to filing any post-effective amendment
       to any registration statement or to supplementing any related prospectus,
       to furnish to the Placement Agent and its counsel, copies of all such
       documents proposed to be amended, filed or supplemented, and (B) it will
       not issue any amendment to the Final Memorandum, any post-effective
       amendment to a registration statement or any supplement to a prospectus
       to which the Placement Agent or its counsel shall reasonably object;

              (4)    it shall notify the Placement Agent and its counsel and (if
       requested by any such person) confirm such advice in writing, (A) when
       any amendment to the Final Memorandum has been issued, when any
       prospectus supplement or amendment or post-effective amendment has been
       filed, and, with respect to any post-effective amendment, when the same
       has become effective, (B) of any request by the SEC for any
       post-


<PAGE>   14

                                       13


       effective amendment or supplement to a registration statement, any
       supplement or amendment to a prospectus or for additional information,
       (C) the issuance by the SEC of any stop order suspending the
       effectiveness of a registration statement or the initiation of any
       proceedings for that purpose, (D) of the receipt by the Company of any
       notification with respect to the suspension of the qualification of the
       Notes or the Exchange Securities for sale in any jurisdiction or the
       initiation or threatening of any proceedings for such purpose and (E) of
       the happening of any event which makes any statement made in the Final
       Memorandum, a registration statement, a prospectus or any amendment or
       supplement thereto untrue or which requires the making of any change in
       the Final Memorandum, a registration statement, a prospectus or any
       amendment or supplement thereto, in order to make the statements therein
       not misleading;

              (5)    it consents to the use of the Final Memorandum and any
       prospectus referred to in this paragraph (k) or any amendment or
       supplement thereto, by the Placement Agent in connection with the
       offering and sale of the Notes or Exchange Securities, as the case may
       be;

              (6)    it will comply with the provisions of this paragraph (k) at
       its own expense and will reimburse the Placement Agent for its expenses
       associated with this paragraph (k) (including fees of counsel); and

              (7)    it expressly acknowledges that the indemnification and
       contribution provisions of Section 8 of this Agreement shall be
       specifically applicable and relate to each offering memorandum,
       registration statement, prospectus, amendment or supplement referred to
       in this paragraph (k).

              (l)    to make or cause to be made an application to list the
       Notes on the Luxembourg Stock Exchange within 45 days after the Closing
       Date and thereafter to use best efforts to obtain such listing.

              7.     Offering of Notes; Restrictions on Transfer. The Placement
Agent represents and warrants that it is a qualified institutional buyer as
defined in Rule 144A under the Securities Act (a "QIB"). The Placement Agent
agrees with the Company that (i) it will not solicit offers for, or offer or
sell, the Notes by any form of general solicitation or general advertising (as
those terms are used in Regulation D under the Securities Act) or in any manner
involving a public offering within the meaning of Section 4(2) of the Securities
Act and (ii) it will solicit offers for the Notes only from, and will offer the
Notes only to, persons that it reasonably believes to be QIBs that, in
purchasing the Notes are deemed to have represented and agreed as provided in
the Final Memorandum under the caption "Transfer Restrictions."

              8.     Indemnification and Contribution. (a) The Company agrees to
indemnify and hold harmless the Placement Agent, and each person, if any, who
controls the Placement Agent within the meaning of either Section 15 of the
Securities Act or Section 20 of the


<PAGE>   15

                                       14


Exchange Act, or is under common control with, or is controlled by, the
Placement Agent, from and against any and all losses, claims, damages and
liabilities (including, without limitation, any legal or other expenses
reasonably incurred by the Placement Agent or any such controlling or affiliated
person in connection with defending or investigating any such action or claim)
caused by any untrue statement or alleged untrue statement of a material fact
contained in either Memorandum (as amended or supplemented if the Company shall
have furnished any amendments or supplements thereto), or caused by any omission
or alleged omission to state therein a material fact necessary to make the
statements therein in light of the circumstances under which they were made not
misleading, except insofar as such losses, claims, damages or liabilities are
caused by any such untrue statement or omission or alleged untrue statement or
omission based upon information relating to the Placement Agent furnished to the
Company in writing by the Placement Agent through you expressly for use therein.

              (b)    The Placement Agent agrees to indemnify and hold harmless
the Company and its directors, officers and each person, if any, who controls
the Company within the meaning of either Section 15 of the Securities Act or
Section 20 of the Exchange Act to the same extent as the foregoing indemnity
from the Company to the Placement Agent, but only with reference to information
relating to such Placement Agent furnished to the Company in writing by the
Placement Agent through you expressly for use in either Memorandum or any
amendments or supplements thereto.

              (c)    In case any proceeding (including any governmental
investigation) shall be instituted involving any person in respect of which
indemnity may be sought pursuant to Section 8(a) or 8(b), such person (the
"indemnified party") shall promptly notify the person against whom such
indemnity may be sought (the "indemnifying party") in writing and the
indemnifying party, upon request of the indemnified party, shall retain counsel
reasonably satisfactory to the indemnified party to represent the indemnified
party and any others the indemnifying party may designate in such proceeding and
shall pay the fees and disbursements of such counsel related to such proceeding.
In any such proceeding, any indemnified party shall have the right to retain its
own counsel, but the fees and expenses of such counsel shall be at the expense
of such indemnified party unless (i) the indemnifying party and the indemnified
party shall have mutually agreed to the retention of such counsel or (ii) the
named parties to any such proceeding (including any impleaded parties) include
both the indemnifying party and the indemnified party and representation of both
parties by the same counsel would be inappropriate due to actual or potential
differing interests between them. It is understood that the indemnifying party
shall not, in respect of the legal expenses of any indemnified party in
connection with any proceeding or related proceedings in the same jurisdiction,
be liable for the fees and expenses of more than one separate firm (in addition
to any local counsel) for all such indemnified parties and that all such fees
and expenses shall be reimbursed as they are incurred. Such firm shall be
reasonably satisfactory to the Placement Agent, in the case of parties
indemnified pursuant to Section 8(a) above and reasonably satisfactory to the
Company, in the case of parties indemnified pursuant to Section 8(b) above. The
indemnifying party shall not be liable for any settlement of any proceeding
effected without its written consent, but if settled with such consent or if
there be a final judgment for the plaintiff, the indemnifying party agrees to
indemnify the


<PAGE>   16


                                       15


indemnified party from and against any loss or liability by reason of such
settlement or judgment. Notwithstanding the foregoing sentence, if at any time
an indemnified party shall have requested an indemnifying party to reimburse the
indemnified party for fees and expenses of counsel as contemplated by the second
and third sentences of this paragraph, the indemnifying party agrees that it
shall be liable for any settlement of any proceeding effected without its
written consent if (i) such settlement is entered into more than 30 days after
receipt by such indemnifying party of the aforesaid request and (ii) such
indemnifying party shall not have reimbursed the indemnified party in accordance
with such request prior to the date of such settlement. No indemnifying party
shall, without the prior written consent of the indemnified party, effect any
settlement of any pending or threatened 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 proceeding.

              (d)    To the extent the indemnification provided for in Section
8(a) or 8(b) of this Section 8 is unavailable to an indemnified party or
insufficient in respect of any losses, claims, damages or liabilities referred
to therein, then each indemnifying party under such paragraph, in lieu of
indemnifying such indemnified party thereunder, shall contribute to the amount
paid or payable by such indemnified party as a result of such losses, claims,
damages or liabilities (i) in such proportion as is appropriate to reflect the
relative benefits received by the Company, on the one hand, and the Placement
Agent, on the other hand, from the offering of such Notes or (ii) if the
allocation provided by clause 8(a)(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 8(a)(i) above but also the relative fault of the Company,
on the one hand, and the Placement Agent, on the other hand, in connection with
the statements or omissions that resulted in such losses, claims, damages or
liabilities, as well as any other relevant equitable considerations. The
relative benefits received by the Company, on the one hand, and the Placement
Agent, on the other hand, in connection with the offering of such Notes shall be
deemed to be in the same respective proportions as the net proceeds from the
offering of such Notes (before deducting expenses) received by the Company and
the total discounts and commissions received by the Placement Agent in respect
thereof bear to the aggregate offering price of such Notes. The relative fault
of the Company, on the one hand, and of the Placement Agent, 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 by
the Placement Agent and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.

              (e)    The Company and the Placement Agent agree that it would not
be just or equitable if contribution pursuant to this Section 8 were determined
by pro rata allocation or by any other method of allocation that does not take
account of the equitable considerations referred to in paragraph (d) above. The
amount paid or payable by an indemnified party as a result of the losses,
claims, damages and liabilities referred to in paragraph (d) above shall be
deemed to


<PAGE>   17

                                       16


include, subject to the limitations set forth above, any legal or other expenses
reasonably incurred by such indemnified party in connection with investigating
or defending any such action or claim. Notwithstanding the provisions of this
Section 8, the Placement Agent shall not be required to contribute any amount in
excess of the amount by which the total price at which the Notes resold by it in
the initial placement of such Notes were offered to investors exceeds the amount
of any damages that the Placement Agent has otherwise been required to pay by
reason of such untrue or alleged untrue statement or omission or alleged
omission. No person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) shall be entitled to contribution from
any person who was not guilty of such fraudulent misrepresentation. The
indemnity and contribution provisions contained in this Section 8 and the
representations and warranties and other statements of the Company contained in
this Agreement shall remain operative and in full force and effect regardless of
(i) any termination of this Agreement, (ii) any investigation made by or on
behalf of the Placement Agent or any person controlling the Placement Agent or
by or on behalf of the Company or its officers or directors or any person
controlling the Company and (iii) acceptance of and payment for any of the
Notes. The remedies provided for in this Section 8 are not exclusive and shall
not limit any rights or remedies which may otherwise be available to any
indemnified party at law or in equity.

              9.     Termination. This Agreement shall be subject to termination
by notice given by you to the Company, if (a) after the execution and delivery
of this Agreement and prior to the Closing Date (i) trading generally shall have
been suspended or materially limited on or by, as the case may be, any of the
New York Stock Exchange, the American Stock Exchange or the National Association
of Securities Dealers, Inc., the Chicago Board of Options Exchange, the Chicago
Mercantile Exchange or the Chicago Board of Trade, (ii) trading of any
securities of the Company shall have been suspended on any exchange or in any
over-the-counter market, (iii) a general moratorium on commercial banking
activities in New York shall have been declared by either Federal or New York
State authorities or (iv) there shall have occurred any outbreak or escalation
of hostilities or any change in financial markets or any calamity or crisis
that, in your judgment, is material and adverse and (b) in the case of any of
the events specified in clauses 9(a)(i) through 9(a)(iv), such event, singly or
together with any other such event makes it, in your judgment, impracticable to
market the Notes on the terms and in the manner contemplated in the Final
Memorandum.

              10.    Effectiveness; Payment of Expenses Upon Termination. This
Agreement shall become effective upon the execution and delivery hereof by the
parties hereto.

              If this Agreement shall be terminated by the Placement Agent
because of any failure or refusal on the part of the Company to comply with the
terms or to fulfill any of the conditions of this Agreement, or if for any
reason the Company shall be unable to perform its obligations under this
Agreement, the Company will reimburse the Placement Agent for all out-of-pocket
expenses (including the fees and disbursements of their counsel) reasonably
incurred by the Placement Agent in connection with this Agreement or the
offering contemplated hereunder.


<PAGE>   18

                                       17


              11.    Notices. All notices and other communications under this
Agreement shall be in writing and mailed, delivered or sent by facsimile
transmission to: if sent to the Placement Agent, Morgan Stanley & Co.
Incorporated, 1585 Broadway, New York, New York 10036, Attention: High Yield New
Issues Group, facsimile number (212) 761-0587 and if sent to the Company, to
Alferez Pareja 256, 1107 Buenos Aires, Argentina, attention: Chief Financial
Officer, facsimile number 011 (541) 307 1525.

              12.    Counterparts. This Agreement may be signed in any number of
counterparts, each of which shall be an original, with the same effect as if the
signatures thereto and hereto were upon the same instrument.

              13.    Applicable Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of New York.

              14.    Headings. The headings of the sections of this Agreement
have been inserted for convenience of reference only and shall not be deemed a
part of this Agreement.


<PAGE>   19

              Please confirm your agreement to the foregoing by signing in the
space provided below for that purpose and returning to us a copy hereof,
whereupon this Agreement shall constitute a binding agreement between us.

                                          Very truly yours,

                                          IMPSAT FIBER NETWORKS, INC.

                                          By  /s/ RICARDO A. VERDAGUER
                                            ------------------------------------
                                            Name: Ricardo A. Verdaguer

Title:  President and Chief Executive

                                                 Officer

                                          By  /s/ GUILLERMO JOFRE
                                            ------------------------------------
                                            Name:  Guillermo Jofre
                                            Title: Chief Financial Officer

Accepted as of the date hereof

MORGAN STANLEY & CO. INCORPORATED

By:  Morgan Stanley & Co. Incorporated

By  /s/ JOHN D. TYREE
  -------------------
  Name:  John D. Tyree
  Title: Vice President


<PAGE>   20


                                                                       EXHIBIT A

                           Opinion of Arnold & Porter

              (A)    the Company has been duly incorporated, is validly existing
as a corporation in good standing under the laws of the State of Delaware, and
has the corporate power and authority to own its property and to conduct its
business as described in the Final Memorandum (references herein to the Final
Memorandum being taken to mean the same, as amended or supplemented);

              (B)    the Placement Agreement has been duly authorized, executed
and delivered by the Company;

              (C)    the Indenture has been duly authorized, executed and
delivered by the Company and is a valid and binding agreement of the Company,
enforceable in accordance with its terms;

              (D)    the Registration Rights Agreement has been duly authorized,
executed and delivered by the Company and is a valid and binding agreement of
the Company, enforceable against the Company in accordance with its terms;

              (E)    the Notes have been duly authorized by the Company, and
when executed, authenticated and delivered in accordance with the terms of the
Indenture and paid for in accordance with the terms of the Placement Agreement,
will constitute valid and binding obligations of the Company enforceable against
the Company in accordance with their terms, and will be entitled to the benefits
of the Indenture and the Registration Rights Agreement;

              (F)    the execution and delivery by the Company of, and the
performance by the Company of its obligations under, the Placement Agreement,
the Indenture, the Registration Rights Agreement, the Notes, and the issuance,
sale and delivery of the Notes, will not result in a breach or violation of any
of the terms or provisions of, or constitute a default under, (i) the
certificate of incorporation or bylaws of the Company, as amended to date, (ii)
to such counsel's knowledge, any statute, rule, regulation or order of general
applicability of any United States federal, New York or Delaware governmental
agency, body or court, (iii) to such counsel's knowledge, any judgment, decree
or order of any United States federal, New York or Delaware governmental agency,
body or court or (iv) any of the agreements or instruments listed in Schedule 1
hereto;

              (G)    no consent, approval, authorization or order of, or
qualification with any court or governmental agency or body of the United
States, New York or Delaware is required for the performance by the Company of
its obligations under the Placement Agreement, the Indenture, the Registration
Rights Agreement, the Notes, or the issuance, sale and delivery of the


<PAGE>   21


                                      A-2


Notes, except in each case as may be required by the securities or Blue Sky laws
of the various states in connection with the offer and sale of the Notes;

              (H)    after due inquiry, such counsel does not know of any legal
or governmental proceedings pending or threatened in the United States to which
the Company or any of its subsidiaries is a party or to which any of the
properties of the Company or any of its subsidiaries is subject other than
proceedings fairly summarized in the Final Memorandum and proceedings which such
counsel believes are not likely to have a material adverse effect on the Company
and its subsidiaries, taken as a whole, or on the power or ability of the
Company to perform its obligations under the Placement Agreement, the Indenture,
the Registration Rights Agreement or the Notes or to consummate the transactions
contemplated by the Placement Agreement, the Indenture, the Registration Rights
Agreement and the Notes;

              (I)    the Company is not, and after giving effect to the offering
and sale of the Notes and the application of the proceeds thereof as described
in the Final Memorandum under the caption "Use of Proceeds", will not be an
"investment company" within the meaning of the United States Investment Company
Act of 1940, as amended (the "Investment Company Act"), and the offer and sale
of the Notes in the manner contemplated by the Placement Agreement does not
require registration of the Company as an "investment company" under the
Investment Company Act;

              (J)    the statements set forth in the Final Memorandum under the
captions "Description of the Notes", "Private Placement", "Description of Our
Indebtedness", and "Transfer Restrictions" insofar as such statements constitute
a summary of the legal matters and documents referred to therein, accurately
summarize such matters and documents in all material respects;

              (K)    the discussion set forth in the Final Memorandum, under the
caption "Certain U.S. Federal Income Tax Considerations" to the extent such
discussion constitutes matters of law or legal conclusions, accurately describes
the material United States federal income tax consequences of an investment in
the Notes;

              (L)    such counsel believes that (except for financial statements
and other financial data as to which such counsel need not express any belief)
the Final Memorandum when issued did not, and as of the date such opinion is
delivered does not, contain any untrue statement of a material fact or omit to
state a material fact necessary in order to make the statements therein, in the
light of the circumstances under which they were made, not misleading;

              (M)    based upon the representations, warranties, and agreements
of the Company in the Placement Agreement and of the Placement Agent in the
Placement Agreement, it is not necessary in connection with the offer, sale and
delivery of the Notes to the Placement Agent under the Placement Agreement or in
connection with the initial resale of such Notes by


<PAGE>   22

                                      A-3


the Placement Agent in accordance with the Placement Agreement to register the
Notes under the Securities Act of 1933, it being understood that no opinion is
expressed as to any subsequent resale of any Notes; and

              With respect to paragraph (L) above, counsel may state that their
opinion and belief are based upon their participation in the preparation of the
Final Memorandum (and any amendments or supplements thereto) and review and
discussion of the contents thereof, but are without independent check or
verification except with respect to paragraphs (J) and (K) above.


<PAGE>   23


                                                                       EXHIBIT B

                           Opinion of Nicholson & Cano

              (A)    IMPSAT Argentina has been duly incorporated, is validly
existing as a corporation in good standing under the laws of the Republic of
Argentina, has the corporate power and authority to own its property and to
conduct its business as described in the Final Memorandum and is duly qualified
to transact business and is in good standing in each jurisdiction in which the
conduct of its business or its ownership or leasing of property requires such
qualification, except to the extent that the failure to be so qualified or be in
good standing would not have a material adverse effect on the Company and its
subsidiaries taken as a whole;

              (B)    all of the shares of capital stock of IMPSAT Argentina
owned by the Company have been duly and validly authorized and issued and are
fully paid and non-assessable and are directly owned by the Company, free and
clear of all liens, encumbrances, equities or claims;

              (C)    IMPSAT Argentina has all necessary certificates, orders,
permits, licenses, authorizations, consents and approvals of and from, and has
made all declarations and filings with, all Argentine governmental authorities,
courts and tribunals, to own, lease, license and use its properties and assets
and to conduct its business in the manner described in the Final Memorandum, and
IMPSAT Argentina has not received any notice of proceedings relating to
revocation or modification of any such certificates, orders, permits, licenses,
authorizations, consents or approvals, nor is IMPSAT Argentina in violation of,
or in default under, any federal, state, local, foreign supranational, national
or regional law, regulation, rule, decree, order or judgment applicable to
IMPSAT Argentina the effect of which, singly or in the aggregate, would have a
material adverse effect on the prospects, condition, financial or otherwise, or
in the earnings, business or operations of the Company and its subsidiaries,
taken as a whole, except as described in the Final Memorandum;

              (D)    the statements in the Final Memorandum under the caption
"Risk Factors -- We face regulatory risks and uncertainty with respect to local
laws and regulations", "Business -- Legal Matters" and "Business -- Description
of Country Operations -- IMPSAT Argentina" in each case insofar as such
statements constitute summaries of the Argentine legal matters, documents or
proceedings referred to therein, are accurate in all material respects and
fairly summarize all matters referred to therein;

              (E)    There are no restrictions (legal, contractual or otherwise)
on the ability IMPSAT Argentina to declare and pay any dividends or make any
payment or transfer of property or assets to its stockholders other than those
referred to in the Final Memorandum (including, without limitation, the
description of withholding taxes contained therein) and any applicable
creditors' rights under Argentine law, and such restrictions as would not have a
material adverse effect on the prospects, condition, financial or otherwise, or
in the earnings,


<PAGE>   24

                                      B-2


business or operations of the Company and its subsidiaries, taken as a whole;
and such descriptions, if any, fairly summarize such restrictions, provided
however that such dividends may be delcared (i) out of positive retained
earnings determined in accordance with local generally accepted accounting
principles as reflected in duly approved financial statements of IMPSAT
Argentina and (ii) pursuant to Article 27 of IMPSAT Argentina's by-laws; and

              (F)    after due inquiry, such counsel does not know of any legal
or governmental proceedings pending or threatened in Argentina to which IMPSAT
Argentina is a party or to which any of the properties of IMPSAT Argentina is
subject other than proceedings fairly summarized in the Final Memorandum and
proceedings which such counsel believes are not likely to have a material
adverse effect on the Company and its subsidiaries, taken as a whole, or on the
power or ability of the Company to perform its obligations under this Agreement
or to consummate the transactions contemplated by this Agreement.


<PAGE>   25


                                                                       EXHIBIT C

                   Opinion of S.E. Consultores Asociados Ltda.

              (A)    IMPSAT Colombia has been duly incorporated, is validly
existing as a corporation in good standing under the laws of the Republic of
Colombia, has the corporate power and authority to own its property and to
conduct its business as described in the Final Memorandum and is duly qualified
to transact business and is in good standing in each jurisdiction in which the
conduct of its business or its ownership or leasing of property requires such
qualification, except to the extent that the failure to be so qualified or be in
good standing would not have a material adverse effect on the Company and its
subsidiaries taken as a whole;

              (B)    all of the shares of capital stock of IMPSAT Colombia owned
by the Company have been duly and validly authorized and issued and are fully
paid and non-assessable and are directly owned by the Company, free and clear of
all liens, encumbrances, equities or claims;

              (C)    IMPSAT Colombia has all necessary certificates, orders,
permits, licenses, authorizations, consents and approvals of and from, and has
made all declarations and filings with, all Colombian governmental authorities,
courts and tribunals, to own, lease, license and use its properties and assets
and to conduct its business in the manner described in the Final Memorandum, and
IMPSAT Colombia has not received any notice of proceedings relating to
revocation or modification of any such certificates, orders, permits, licenses,
authorizations, consents or approvals, nor is IMPSAT Colombia in violation of,
or in default under, any federal, state, local, foreign supranational, national
or regional law, regulation, rule, decree, order or judgment applicable to
IMPSAT Colombia the effect of which, singly or in the aggregate, would have a
material adverse effect on the prospects, condition, financial or otherwise, or
in the earnings, business or operations of the Company and its subsidiaries,
taken as a whole, except as described in the Final Memorandum;

              (D)    the statements in the Final Memorandum under the caption
"Business -- Description of Country Operations - IMPSAT Colombia" insofar as
such statements constitute summaries of the Colombian legal matters, documents
or proceedings referred to therein, are accurate in all material respects and
fairly summarize all matters referred to therein;

              (E)    there are no restrictions (legal, contractual or otherwise)
on the ability of IMPSAT Colombia to declare and pay any dividends or make any
payment or transfer of property or assets to its stockholders other than those
referred to in the Final Memorandum (including, without limitation the
description of withholding taxes described therein) and such restrictions as
would not have a material adverse effect on the prospects, condition, financial
or otherwise, or in the earnings, business or operations of the Company and its
subsidiaries, taken as a whole; and such descriptions, if any, fairly summarize
such restrictions; and


<PAGE>   26

                                      C-2


              (F)    after due inquiry, such counsel does not know of any legal
or governmental proceedings pending or threatened in Colombia to which IMPSAT
Colombia is a party or to which any of the properties of IMPSAT Colombia is
subject other than proceedings fairly summarized in the Final Memorandum and
proceedings which such counsel believes are not likely to have a material
adverse effect on the Company and its subsidiaries, taken as a whole, or on the
power or ability of the Company to perform its obligations under this Agreement
or to consummate the transactions contemplated by this Agreement.


<PAGE>   27


                                                                       EXHIBIT D

                       Opinion of Perez Bustamante & Perez

              (A)    IMPSAT Ecuador has been duly incorporated, is validly
existing as a corporation in good standing under the laws of the Republic of
Ecuador, has the corporate power and authority to own its property and to
conduct its business as described in the Final Memorandum dated February 11,
2000 (the "Final Memorandum") and is duly qualified to transact business and is
in good standing in each jurisdiction in which the conduct of its business or
its ownership or leasing of property requires such qualification, except to the
extent that the failure to be so qualified or be in good standing would not have
a material adverse effect on the Company and its subsidiaries taken as a whole;

              (B)    all of the shares of capital stock of IMPSAT Ecuador owned
by the Company have been duly and validly authorized and issued and are fully
paid and non-assessable and are directly owned by the Company, free and clear of
all liens, encumbrances, equities or claims;

              (C)    IMPSAT Ecuador has all necessary certificates, orders,
permits, licenses, authorizations, consents and approvals of and from, and has
made all declarations and filings with, all Ecuadoran governmental authorities,
courts and tribunals, to own, lease, license and use its properties and assets
and to conduct its business in the manner described in the Final Memorandum, and
IMPSAT Ecuador has not received any notice of proceedings relating to revocation
or modification of any such certificates, orders, permits, licenses,
authorizations, consents or approvals, nor is IMPSAT Ecuador in violation of, or
in default under, any federal, state, local, foreign supranational, national or
regional law, regulation, rule, decree, order or judgment applicable to IMPSAT
Ecuador the effect of which, singly or in the aggregate, would have a material
adverse effect on the prospects, condition, financial or otherwise, or in the
earnings, business or operations of the Company and its subsidiaries, taken as a
whole, except as described in the Final Memorandum;

              (D)    the statements in the Final Memorandum under the caption
"Business -- Description of Country Operations -- IMPSAT Ecuador" insofar as
such statements constitute summaries of the legal matters of Ecuador, documents
or proceedings referred to therein, are accurate in all material respects and
fairly summarize all matters referred to therein;

              (E)    There are no restrictions (legal, contractual or otherwise)
on the ability of IMPSAT Ecuador to declare and pay any dividends or make any
payment or transfer of property or assets to its stockholders other than those
referred to in the Final Memorandum (including, without limitation, the
description of withholding taxes contained therein) and such restrictions as
would not have a material adverse effect on the prospects, condition, financial
or otherwise, or in the earnings, business or operations of the Company and its
subsidiaries, taken as a whole; and such descriptions, if any, fairly summarize
such restrictions; and


<PAGE>   28

                                      D-2


              (F)    after due inquiry, such counsel does not know of any legal
or governmental proceedings pending or threatened in Ecuador to which IMPSAT
Ecuador is a party or to which any of the properties of IMPSAT Ecuador is
subject other than proceedings fairly summarized in the Final Memorandum and
proceedings which such counsel believes are not likely to have a material
adverse effect on the Company and its subsidiaries, taken as a whole, or on the
power or ability of the Company to perform its obligations under this Agreement
or to consummate the transactions contemplated by this Agreement.


<PAGE>   29


                                                                       EXHIBIT E

                        Opinion of Basham, Ringe & Correa

              (A)    IMPSAT Mexico has been duly incorporated, is validly
existing as a corporation in good standing under the laws of the jurisdiction of
its organization, has the corporate power and authority to own its property and
to conduct its business as described in the Final Memorandum under the caption
"Business -- Description of Country Operations -- IMPSAT Mexico" and is duly
qualified to transact business and is in good standing in each Mexican
jurisdiction in which the conduct of its business or its ownership or leasing of
property requires such qualification, except to the extent that the failure to
be so qualified or be in good standing would not have a material adverse effect
on the Company taken as a whole;

              (B)    all of the shares of capital stock of IMPSAT Mexico owned
by the Company have been duly and validly authorized and issued and are fully
paid and non-assessable and are directly owned by the Company, free and clear of
all liens, encumbrances, equities or claims;

              (C)    IMPSAT Mexico has all necessary certificates, orders,
permits, licenses, authorizations, consents and approvals of and from, and has
made all declarations and filings with, all Mexican governmental authorities,
all self-regulatory organizations and all courts and tribunals, to own, lease,
license and use its properties and assets and to conduct its business in the
manner described in the Final Memorandum under the caption "Business --
Description of Country Operations -- IMPSAT Mexico" and IMPSAT Mexico has not
received any notice of proceedings relating to revocation or modification of any
such certificates, orders, permits, licenses, authorizations, consents or
approvals, nor is IMPSAT Mexico in violation of, or in default under, any
federal, state, local, foreign supranational, national or regional law,
regulation, rule, decree, order or judgment applicable to IMPSAT Mexico the
effect of which, singly or in the aggregate, would have a material adverse
effect on the prospects, condition, financial or otherwise, or in the earnings,
business or operations of the Company and its subsidiaries, taken as a whole,
except as described in the Final Memorandum;

              (D)    the statements in the Final Memorandum under the caption
"Business -- Description of Country Operations -- IMPSAT Mexico" insofar as such
statements constitute summaries of the Mexican legal matters, documents or
proceedings referred to therein, are accurate in all material respects and
fairly summarize all matters referred to therein;

              (E)    There are no restrictions (legal, contractual or otherwise)
on the ability of IMPSAT Mexico to declare and pay any dividends or make any
payment or transfer of property or assets to its stockholders other than those
referred to in the Final Memorandum (including without limitation, the
description of withholding taxes contained therein) and such restrictions as
would not have a material adverse effect on the prospects, condition, financial
or otherwise, or


<PAGE>   30


                                      E-2


in the earnings, business or operations of the Company and its subsidiaries,
taken as a whole; and such descriptions, if any, fairly summarize such
restrictions; and

              (F)    after due inquiry, such counsel does not know of any legal
or governmental proceedings pending or threatened in Mexico to which IMPSAT
Mexico is a party or to which any of the properties of IMPSAT Mexico is subject
other than proceedings fairly summarized in the Final Memorandum and proceedings
which such counsel believes are not likely to have a material adverse effect on
the Company and its subsidiaries, taken as a whole, or on the power or ability
of the Company to perform its obligations under this Agreement or to consummate
the transactions contemplated by this Agreement.


<PAGE>   31


                                                                       EXHIBIT F

                         Opinion of Baumeister & Brewer

              (A)    IMPSAT Venezuela has been duly incorporated, is validly
existing as a corporation in good standing under the laws of the jurisdiction of
its organization, has the corporate power and authority to own its property and
to conduct its business as described in the Final Memorandum and is duly
qualified to transact business and is in good standing in each jurisdiction in
which the conduct of its business or its ownership or leasing of property
requires such qualification, except to the extent that the failure to be so
qualified or be in good standing would not have a material adverse effect on the
Company and its subsidiaries taken as a whole;

              (B)    all of the shares of capital stock of IMPSAT Venezuela
owned by the Company have been duly and validly authorized and issued and are
fully paid and non-assessable and are directly owned by the Company, free and
clear of all liens, encumbrances, equities or claims;

              (C)    IMPSAT Venezuela has no subsidiaries;

              (D)    IMPSAT Venezuela, to our better knowledge, has all
necessary certificates, orders, permits, licenses, authorizations, consents and
approvals of and from, and has made all declarations and filings with, all
Venezuelan governmental authorities, all self-regulatory organizations and all
courts and tribunals, to own, lease, license and use its properties and assets
and to conduct its business in the manner described in the Final Memorandum. Up
to this date, IMPSAT Venezuela has not received any notice of proceedings
relating to revocation or modification of any such certificates, orders,
permits, licenses, authorizations, consents or approvals, nor is IMPSAT
Venezuela in violation of, or in default under, any federal, state, local,
foreign supranational, national or regional law, regulation, rule, decree, order
or judgment applicable to IMPSAT Venezuela the effect of which, singly or in the
aggregate, would have a material adverse effect on the prospects, condition,
financial or otherwise, or in the earnings, business or operations of the
Company, taken as a whole, except as described in the Final Memorandum;

              (E)    the statements in the Final Memorandum under the captions
(including, without limitation, the description of withholding taxes contained
therein) "Business -- Description of Country Operations -- IMPSAT Venezuela"
insofar as such statements constitute summaries of the Venezuelan legal matters,
documents or proceedings referred to therein, are accurate in all material
respects and fairly summarize all matters referred to therein;

              (F)    There are no restrictions (legal, contractual or otherwise)
on the ability of IMPSAT Venezuela to declare and pay any dividends or make any
payment or transfer of property or assets to its stockholders other than those
referred to in the Final Memorandum (including without limitation the
description of withholding taxes contained therein) and such


<PAGE>   32

                                      F-2


restrictions as would not have a material adverse effect on the prospects,
condition, financial or otherwise, or in the earnings, business or operations of
the Company and its subsidiaries, taken as a whole; and such descriptions, if
any, fairly summarize such restrictions; and

              (G)    after due inquiry, such counsel does not know of any legal
or governmental proceedings pending or threatened in Venezuela to which IMPSAT
Venezuela is a party or to which any of the properties of IMPSAT Venezuela is
subject other than proceedings fairly summarized in the Final Memorandum and
proceedings which such counsel believes are not likely to have a material
adverse effect on the Company and its subsidiaries, taken as a whole, or on the
power or ability of the Company to perform its obligations under this Agreement
or to consummate the transactions contemplated by this Agreement.


<PAGE>   33


                                                                       EXHIBIT G

                            Opinion of Pinheiro Neto

              (A)    IMPSAT Comunicacoes Ltda. ("IMPSAT Brazil") has been duly
incorporated, is validly existing as a corporation in good standing under the
laws of Brazil, has the corporate power and authority to own its property and to
conduct its business as described in the Final Memorandum and is duly qualified
to transact business and is in good standing in each jurisdiction in which the
conduct of its business or its ownership or leasing of property requires such
qualification, except to the extent that the failure to be so qualified or be in
good standing would not have a material adverse effect on the Company and its
subsidiaries as a whole;

              (B)    all of the shares of capital stock of IMPSAT Brazil owned
by the Company have been duly and validly authorized and issued and are fully
paid and non-assessable and are directly owned by the Company, free and clear of
all liens, encumbrances, equities or claims;

              (C)    IMPSAT Brazil has all necessary certificates, orders,
permits, licenses, authorizations, consents and approvals of and from, and has
made all declarations and filings with, all Brazilian governmental authorities,
courts and tribunals, to own, lease, license and use its properties and assets
and to conduct its business in the manner described in the Final Memorandum, and
IMPSAT Brazil has not received any notice of proceedings relating to revocation
or modification of any such certificates, orders, permits, licenses,
authorizations, consents or approvals, nor is IMPSAT Brazil in violation of, or
in default under, any federal, state, local, foreign supranational, national or
regional law, regulation, rule, decree, order or judgment applicable to IMPSAT
Brazil the effect of which, singly or in the aggregate, would have a material
adverse effect on the prospects, condition, financial or otherwise, or in the
earnings, business or operation of the Company and its subsidiaries, taken as a
whole, except as described in the Final Memorandum;

              (D)    the statements in the Final Memorandum under the caption
"Business -- Description of Country Operations -- IMPSAT Brazil" insofar as such
statements constitute summaries of the Brazil legal matters, documents or
proceedings referred to therein, are accurate in all material respects and
fairly summarize all matters referred to therein;

              (E)    there are no restrictions (legal, contractual or otherwise)
on the ability of IMPSAT Brazil to declare and pay any dividends or make any
payment or transfer of property or assets to its stockholders other than those
referred to in the Final Memorandum (including, without limitation, the
description of withholding taxes contained therein) and such restrictions as
would not have a material adverse effect on the prospects, condition, financial
or otherwise, or in the earnings, business or operations of the Company and its
subsidiaries, taken as a whole; and such descriptions, if any, fairly summarize
such restrictions; and


<PAGE>   34


                                       G-2


              (F)    after due inquiry, such counsel does not know of any legal
or governmental proceedings pending or threatened in Brazil to which IMPSAT
Brazil is a party or to which any of the properties of IMPSAT Brazil is subject
other than proceedings fairly summarized in the Final Memorandum and proceedings
which such counsel believes are not likely to have a material adverse effect on
the Company and its subsidiaries, taken as a whole, or on the power or ability
of the Company to perform its obligations under this Agreement or to consummate
the transactions contemplated by this Agreement.


<PAGE>   35


                                                                       EXHIBIT H

                           Opinion of Latham & Watkins

              (A)    the execution and delivery by the Company of the Placement
Agreement, the Indenture, the Registration Rights Agreement and the Notes, and
the performance by the Company of its obligations thereunder in accordance with
the terms thereof, (i) do not require any consent, approval, authorization or
other order of the Federal Communications Commission ("FCC") and (ii) do not
violate the Federal Communications Act of 1934, as amended (the "Communications
Act") or the rules, regulations and published policies of the FCC;

              (B)    IMPSAT USA, Inc. holds the FCC licenses, permits and
authorizations set forth in Attachment 1 (the "FCC Licenses"). The FCC Licenses
are in full force and effect. The FCC Licenses are not subject to any conditions
outside the ordinary course;

              (C)    based on such counsel's review of the FCC files relating to
the Company and IMPSAT USA, Inc., publicly available on February 15, 2000, and
informal and non binding statements and representations of members of staff of
the FCC, and to the best of such counsel's knowledge, there is no pending
threatened proceeding or action by or before the FCC to revoke, cancel, rescind
or adversely modify any of the FCC Licenses, except for proceedings affecting
the telecommunications or satellite industries generally;

              (D)    the statements in the Final Memorandum under the caption
"Business -- Description of Country Operations -- IMPSAT USA" insofar as such
statements constitute summaries relating to U.S. federal telecommunications
legal matters, and the licenses held by IMPSAT USA, Inc., referred to therein,
are accurate in all material respects.