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                                                                     EXHIBIT 1.1


                              HL&P CAPITAL TRUST I

                  8.125% Trust Preferred Securities, Series A
             guaranteed to the extent set forth in the Guarantee by

                        Houston Lighting & Power Company
                     -------------------------------------

                             Underwriting Agreement
                             ----------------------
                                                            January 30, 1997



Goldman, Sachs & Co.
Merrill Lynch, Pierce, Fenner
 & Smith Incorporated
Dean Witter Reynolds Inc.
Donaldson, Lufkin & Jenrette
 Securities Corporation
A.G. Edwards & Sons, Inc.
PaineWebber Incorporated
Prudential Securities Incorporated
Smith Barney Inc.
As Representatives of the Underwriters
c/o Goldman, Sachs & Co.
85 Broad Street
New York, New York  10004

Ladies and Gentlemen:

          HL&P Capital Trust I, a statutory business trust created under the
laws of the State of Delaware (the "Trust"), and Houston Lighting & Power
Company, a Texas corporation, as depositor of the Trust and as guarantor (the
"Guarantor"),propose, subject to the terms and conditions stated herein, that
the Trust issue and sell to the Underwriters named in Schedule 1 hereto (the
"Underwriters") an aggregate of $250,000,000 liquidation amount of 8.125% Trust
Preferred Securities, Series A (liquidation amount $25 per trust preferred
security) (the "Securities") representing undivided beneficial interests in the
assets of the Trust, guaranteed by the Guarantor as to the payment of
distributions, and as to payments on liquidation or redemption, to the extent
set forth in a guarantee agreement (the "Guarantee") among the Guarantor and The
Bank of New York, as trustee (the "Guarantee Trustee"). The proceeds of the sale
of the Securities and an aggregate of $7,732,000 liquidation amount of its
Common Securities (liquidation amount $25 per common security) (the
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"Common Securities") by the Trust are to be invested in Junior Subordinated
Debentures, Series A (the "Subordinated Debentures") of the Guarantor to be
issued pursuant to a Junior Subordinated Indenture (the "Indenture") among the
Guarantor and The Bank of New York, as trustee (the "Debenture Trustee").

     1.  Representations and Warranties of the Guarantor and the Trust.
         ------------------------------------------------------------- 

         (a) The Guarantor and the Trust jointly and severally represent and
warrant to, and agree with, each of the Underwriters that:

             (i) A registration statement on Form S-3 with respect to the
Securities, the Subordinated Debentures and the Guarantee (File Nos. 333-20069
and 333-20069-01) including a prospectus (any preliminary prospectus included in
such registration statement being hereinafter referred to as a "Preliminary
Prospectus"), copies of which have been delivered to you, has been prepared and
filed by the Guarantor and the Trust with the Securities and Exchange Commission
(the "Commission") and has been declared effective under the Securities Act of
1933, as amended (the "Act").  No stop order suspending the effectiveness of
such registration statement has been issued and no proceeding for that purpose
has been initiated or, to the best knowledge of the Guarantor and the Trust,
threatened by the Commission. Such registration statement (including all
documents filed as part thereof or incorporated by reference therein, but
excluding any Forms T-1, as amended), as amended and supplemented at the date of
this Agreement is hereinafter referred to as to the "Registration Statement."
The Prospectus contained in the Registration Statement at the time that the
Registration Statement was declared effective is hereinafter referred to as the
"Basic Prospectus."

             The prospectus included in the Registration Statement, as amended
and supplemented to the date of this Agreement (including all documents then
incorporated by reference therein and including the Preliminary Supplemented
Prospectus (hereinafter defined) as further supplemented by the Final
Supplemented Prospectus (hereinafter defined)), is hereinafter referred to as
the "Prospectus". Any reference herein to the Registration Statement, the
Prospectus, a Preliminary Prospectus, the Basic Prospectus, the Preliminary
Supplemented Prospectus or the Final Supplemented Prospectus shall be deemed to
refer to and include the documents incorporated by reference therein, or deemed
to be incorporated by reference therein, and filed under the Securities Exchange
Act of 1934, as amended (the "Exchange Act"), on or before the date of such
Registration Statement, Prospectus, Preliminary Prospectus, the Basic

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Prospectus, the Preliminary Supplemented Prospectus or the Final Supplemented
Prospectus.  Any reference herein to the terms "amend", "amendment" or
"supplement" with respect to the Registration Statement or the Prospectus shall
be deemed to refer to and include, without limitation, the filing of any
document under the Exchange Act deemed to be incorporated therein by reference
after the date of such Registration Statement or Prospectus.

             A prospectus supplement, dated, subject to completion, January 27,
1997, as supplemented and amended, is hereinafter called the "Preliminary
Supplemented Prospectus". A prospectus supplement, dated the date hereof,
setting forth the terms of the Securities and of their sale and distribution
(the "Final Supplemented Prospectus") has been prepared and will be filed
pursuant to Rule 424(b) under the Act ("Rule 424(b)").

             (ii)  On the effective date of the Registration Statement, the
Registration Statement, as amended and supplemented at that time, conformed in
all material respects to the requirements of the Act and the Trust Indenture Act
of 1939, as amended (the "TIA"), and the applicable rules and regulations of the
Commission thereunder, and did not include any 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; on the date of the
Preliminary Supplemented Prospectus, the Preliminary Supplemented Prospectus
conformed in all material respects to the requirements of the Act and the TIA
and the applicable rules and regulations of the Commission thereunder, and did
not include any 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; and on the date of this Agreement, the Registration
Statement and the Prospectus conform, and at the Time of Delivery (hereinafter
defined) they will conform, in all material respects to the requirements of the
Act and the TIA and the applicable rules and regulations of the Commission
thereunder, and on the date of this Agreement do not, and on the Time of
Delivery will not, contain any 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;

             (iii) Each document filed or to be filed pursuant to the Exchange
Act and incorporated by reference, or deemed to be incorporated by reference in
the Prospectus (including any document to be filed pursuant to the Exchange Act
which will constitute an amendment to the Prospectus) conformed or, when so
filed, will conform in all material respects to

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the requirements of the Exchange Act and the applicable rules and regulations of
the Commission thereunder, and none of such documents included or, when so
filed, will include any untrue statement of a material fact or omitted or, when
so filed, will omit to state any material fact required to be stated therein or
necessary to make the statements therein, in the light of the circumstances
under which they were made, not misleading;

             (iv)  The Trust has been duly created and is validly existing as a
business trust in good standing under the laws of the State of Delaware, with
power and authority to own, lease and operate its properties and conduct its
business as described in the Prospectus and, based on expected operations and
law in effect on the date hereof, the Trust will be classified as a grantor
trust and will not be classified as an association taxable as a corporation for
United States federal income tax purposes;

             (v) This Agreement has been duly authorized, executed and delivered
by the Guarantor and the Trust;

             (vi) The Securities have been duly authorized by the Trust
Agreement (as defined below), and, when issued and delivered pursuant to this
Agreement, such Securities will be duly and validly issued and, subject to the
qualifications set forth herein, fully paid and non-assessable undivided
beneficial interests in the assets of the Trust entitled to the benefits
provided by the Amended and Restated Trust Agreement (the "Trust Agreement")
among the Guarantor and the Trustees named therein (the "Trustees") (subject to
the terms of the Trust Agreement); provided that the holders of the Securities
("the Securityholders") may be obligated, pursuant to the Trust Agreement, to
(a) provide indemnity and/or security in connection with and pay taxes or
governmental charges arising from transfers or exchanges of Securities
certificates and the issuance of replacement Securities certificates and (b)
provide security and indemnity in connection with requests of or directions to
the Property Trustee (as defined in the Trust Agreement) to exercise its rights
and remedies under the Trust Agreement; and the Securities conform to the
description thereof contained in the Final Supplemented Prospectus;

             (vii) The Securityholders will be entitled to the same limitation
of personal liability extended to stockholders of private corporations for
profit organized under the General Corporation Law of the State of Delaware;

             (viii) The Common Securities have been duly authorized by the Trust
Agreement, and upon delivery by the Trust to the Guarantor against payment
therefor as set forth

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in the Trust Agreement, will be duly and validly issued and undivided beneficial
interests in the assets of the Trust and conform to the description thereof
contained in the Final Supplemented Prospectus; the issuance of the Common
Securities of the Trust is not subject to preemptive or other similar rights;
and at the Time of Delivery, all of the issued and outstanding Common Securities
will be directly owned by the Guarantor free and clear of any security interest,
mortgage, pledge, lien, encumbrance, claim or equity;

             (ix) The Guarantee, the Trust Agreement, the Subordinated
Debentures, the Indenture and the Agreement as to Expenses and Liabilities
between the Guarantor and the Trust (the "Expense Agreement") (the Guarantee,
the Trust Agreement, the Subordinated Debentures, the Indenture and the Expense
Agreement being collectively referred to as the "Guarantor Agreements") have
each been duly authorized by the Guarantor and when validly executed and
delivered by the Guarantor and, in the case of the Guarantee, by the Guarantee
Trustee, in the case of the Trust Agreement, by the Trustees and, in the case of
the Indenture, by the Debenture Trustee, and, in the case of the Subordinated
Debentures, when validly issued by the Guarantor and duly authenticated and
delivered by the Debenture Trustee, will constitute valid and legally binding
obligations of the Guarantor and the respective trustees, enforceable in
accordance with their respective terms, subject, as to enforcement, to
bankruptcy, insolvency, reorganization and other laws of general applicability
relating to or affecting creditors' rights and to general equity principles
(regardless of whether such enforceability is considered in a proceeding in
equity or at law); the Subordinated Debentures when validly issued by the
Guarantor and duly authenticated and delivered by the Debenture Trustee, will be
entitled to the benefits of the Indenture; and the Guarantor Agreements conform
to the descriptions thereof in the Final Supplemented Prospectus;

             (x) The issue and sale of the Securities by the Trust, the
compliance by the Trust with all of the provisions of this Agreement, the
Securities and the Trust Agreement, the purchase of the Subordinated Debentures
by the Trust, the execution, delivery and performance by the Trust of the Trust
Agreement and the consummation of the transactions contemplated herein and
therein will not conflict with or result in a breach or violation of any of the
terms or provisions of, or constitute a default under, any indenture, mortgage,
deed of trust, loan agreement or other agreement or instrument to which the
Trust is a party or by which the Trust is bound or to which any of the property
or assets of the Trust is subject, nor will such action result in any violation
of the provisions of the

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Trust Agreement or any existing statute or any order, rule or regulation of any
court or governmental agency or body having jurisdiction over the Trust or any
of its properties; the Commission has issued an order under the Act declaring
the Registration Statement effective and qualifying the Guarantee, the Trust
Agreement and the Indenture under the TIA and no other consent, approval,
authorization, order, registration or qualification of or with any such court or
governmental agency or body is required for the issue and sale of the Securities
and the Common Securities by the Trust, the purchase of the Subordinated
Debentures by the Trust or the consummation by the Trust of the transactions
contemplated by this Agreement, except such consents, approvals, authorizations,
registrations or qualifications as may be required under state securities or
Blue Sky laws in connection with the purchase and distribution of the Securities
by the Underwriters;

             (xi) The issuance by the Guarantor of the Guarantee and the
Subordinated Debentures, the compliance by the Guarantor with all of the
provisions of this Agreement, the Guarantee, the Subordinated Debentures, the
Trust Agreement, the Indenture and the Expense Agreement, the execution,
delivery and performance by the Guarantor of the Guarantor Agreements, and the
consummation of the transactions contemplated herein and therein will not
conflict with or result in a breach or violation of any of the terms or
provisions of, or constitute a default under, any indenture, mortgage, deed of
trust, loan agreement or other agreement or instrument for borrowed money to
which the Guarantor or any Significant Subsidiary (as defined by Regulation S-X)
of the Guarantor (each, a "Significant Subsidiary") is a party or by which the
Guarantor or any Significant Subsidiary is bound or to which any of the property
or assets of the Guarantor or any Significant Subsidiary is subject, nor will
such action result in any violation of the provisions of the Restated Articles
of Incorporation or Amended and Restated By-laws of the Guarantor or any
existing statute or any order, rule or regulation of any court or governmental
agency or body having jurisdiction over the Guarantor or any of its or its
Significant Subsidiaries' properties; the Commission has issued an order under
the Act declaring the Registration Statement effective and qualifying the
Guarantee, the Trust Agreement and the Indenture under the TIA and no other
consent, approval, authorization, order, registration or qualification of or
with any such court or governmental agency or body is required for the issue of
the Guarantee or the Subordinated Debentures or the consummation by the
Guarantor of the other transactions contemplated by this Agreement or the
Guarantor Agreements, except such consents, approvals, authorizations,
registrations or qualifications as may be required under state securities or
Blue Sky laws

                                       6
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in connection with the issuance by the Guarantor of the Guarantee and the
Subordinated Debentures;

             (xii) The Trust is not and, after giving effect to the offering and
sale of the Securities, will not be an "investment company", or an entity
"controlled" by an "investment company", as such terms are defined in the
Investment Company Act of 1940, as amended (the "Investment Company Act");

       2.  Sale and Delivery.
           ----------------- 

           (a)  Subject to the terms and conditions herein set forth, the
Guarantor and the Trust agree to issue and sell to each of the Underwriters, and
each of the Underwriters agrees, severally and not jointly, to purchase from the
Trust, at a purchase price of 100% of the liquidation amount thereof, the
liquidation amount of Securities set forth opposite the name of such
Underwriters in Schedule I hereto.

           (b) As compensation to the Underwriters for their commitments
hereunder, and in view of the fact that the proceeds of the sale of the
Securities will be issued by the Trust to purchase the Subordinated Debentures
of the Guarantor, the Guarantor hereby agrees to pay at the Time of Delivery to
Goldman, Sachs & Co., for the accounts of the several Underwriters, an amount
equal to $0.7875 per Security for the Securities to be delivered at the Time of
Delivery by wire transfer of Federal (same-day) funds.  The total aggregate
amount of the Underwriters' compensation is $7,875,000.

           (c) The Securities to be purchased by each Underwriter hereunder will
be represented by one or more definitive global Securities in book-entry form
which will be deposited by or on behalf of the Trust with The Depository Trust
Company ("DTC") or its designated custodian.  The Trust will deliver the
Securities to Goldman, Sachs & Co., for the account of each Underwriter, against
payment by or on behalf of such Underwriter of the purchase price therefor by
wire transfer of Federal (same day) funds to a commercial bank account located
in the United States and designated in writing at least forty-eight hours prior
to the Time of Delivery by the Guarantor to Goldman, Sachs & Co., by causing DTC
to credit the Securities to the account of Goldman, Sachs & Co. at DTC. The
Trust will cause the global certificates representing the Securities to be made
available to Goldman, Sachs & Co. for checking at least twenty-four hours prior
to the Time of Delivery at the office of DTC or its designated custodian (the
"Designated Office"). The time and date of such delivery and payment shall be
9:30 a.m., New York City time,

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on Tuesday, February 4, 1997 or such other time and date as Goldman, Sachs & Co.
and the Guarantor may agree upon in writing. Such time and date are herein
called the "Time of Delivery".

           (d) The documents to be delivered at the Time of Delivery by or on
behalf of the parties hereto pursuant to Section 5 hereof, including the cross-
receipt for the Securities and any additional documents requested by the
Underwriters pursuant to Section 5(j) hereof, will be delivered at such time and
date at the offices of Dewey Ballantine, 1301 Avenue of the Americas, New York,
New York 10019 or such other location as Goldman, Sachs & Co. and the Guarantor
may agree in writing (the "Closing Location"), and the Securities will be
delivered at the Designated Office, all at the Time of Delivery. A meeting will
be held at the Closing Location at 1:00 p.m., New York City time or at such
other time as Goldman, Sachs & Co. and the Guarantor may agree in writing, on
the New York Business Day next preceding the Time of Delivery, at which meeting
the final drafts of the documents to be delivered pursuant to the preceding
sentence will be available for review by the parties hereto.  For the purposes
of this Section 2, "New York Business Day" shall mean each Monday, Tuesday,
Wednesday, Thursday and Friday which is not a day on which banking institutions
in New York are generally authorized or obligated by law or executive order to
close.

       3.  Covenants and Agreements.
           ------------------------- 

           The Guarantor and the Trust jointly and severally covenant and agree
with each of the Underwriters:

           (a)  That the Guarantor will furnish without charge to the
Underwriters a copy of the Registration Statement, including all documents
incorporated by reference therein and exhibits filed with the Registration
Statement (other than exhibits which are incorporated by reference and have
previously been so furnished), and, during the period mentioned in paragraph (c)
below, as many copies of the Prospectus, the Preliminary Supplemented Prospectus
and the Final Supplemented Prospectus, any documents incorporated by reference
therein at or after the date thereof (including documents from which information
has been so incorporated) and any supplements and amendments thereto as each
Underwriter may reasonably request so long as such Underwriter is required to
deliver a prospectus;

           (b)  That the Guarantor will cause the Final Supplemented Prospectus
to be filed pursuant to, and in compliance with, Rule 424(b) and will promptly
advise the Underwriters (i) when any amendment to the Registration Statement
shall have been filed; provided, that, with

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respect to documents filed pursuant to the Exchange Act and incorporated by
reference into the Registration Statement, such notice shall only be required
during such time as the Underwriters are required in the reasonable opinion of
Dewey Ballantine, counsel for the Underwriters, to deliver a prospectus, (ii) of
any request by the Commission for any amendment of the Registration Statement,
(iii) of the issuance by the Commission of any stop order suspending the
effectiveness of the Registration Statement or the institution or threatening of
any proceeding for that purpose, and (iv) of the receipt by the Guarantor or the
Trust of any notification with respect to the suspension of the qualification of
the Securities for sale in any jurisdiction or the initiation or threatening of
any proceeding for such purpose. So long as any Underwriter is required in the
reasonable opinion of Dewey Ballantine to deliver a prospectus, the Guarantor
will not file any amendment to the Registration Statement or supplement to the
Prospectus unless the Guarantor has furnished one copy of such amendment or
supplement to Goldman, Sachs & Co. and to Dewey Ballantine, and, if such
amendment or supplement is to be filed on or prior to the Time of Delivery, or
under circumstances where the Underwriters are required in the reasonable
opinion of Dewey Ballantine, to deliver a Prospectus, the Underwriters or Dewey
Ballantine, shall not reasonably have objected thereto. If the Commission shall
issue a stop order suspending the effectiveness of the Registration Statement,
the Guarantor will take such steps to obtain the lifting of that order as in the
best judgment of the Guarantor are not contrary to the interests of the
Guarantor;

           (c) That if, at any time when in the reasonable opinion of Dewey
Ballantine the Prospectus is required by law to be delivered by an Underwriter
or a dealer, any event shall occur as a result of which it is necessary, in the
reasonable opinion of Dewey Ballantine or counsel for the Guarantor, to amend or
supplement the Prospectus or modify the information incorporated by reference
therein in order to make the statements therein, in light of the circumstances
existing when the Prospectus is delivered to a purchaser, not misleading, or if
it shall be necessary in the reasonable opinion of any such counsel, to amend or
supplement the Prospectus or modify such information to comply with law, the
Guarantor will forthwith (i) prepare and furnish, at its own expense, to the
Underwriters and to the dealers (whose names and addresses the Underwriters will
furnish to the Guarantor) to whom Securities may have been sold by the
Underwriters and to any other dealers upon reasonable request, either amendments
or supplements to the Prospectus or (ii) file with the Commission documents
incorporated by reference in the Prospectus, which shall be so supplied to the
Underwriters and such dealers, in either

                                       9
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case so that the statements in the Prospectus as so amended, supplemented or
modified will not, in light of the circumstances when the Prospectus is
delivered to a purchaser, be misleading or so that the Prospectus will comply
with law;

           (d) That the Guarantor will endeavor to qualify, at its expense, the
Securities, and, to the extent required or advisable, the Guarantee and the
Subordinated Debentures, for offer and sale under the securities or Blue Sky
laws of such jurisdictions as the Underwriters shall reasonably request and to
pay all filing fees, reasonable expenses and legal fees in connection therewith
and in connection with the determination of the eligibility for investment of
the Securities; provided, that the Guarantor shall not be required to qualify as
a foreign corporation or a dealer in securities or to file any consents to
service of process under the laws of any jurisdiction;

           (e) That the Guarantor will make generally available to its security
holders and the Securityholders as soon as practicable an earnings statement of
the Guarantor covering a twelve-month period beginning after the Time of
Delivery which shall satisfy the provisions of Section 11(a) of the Act and the
rules and regulations of the Commission thereunder (including Rule 158 under the
Act).

           (f)  That during the period beginning on the date of this Agreement
and continuing to and including the Time of Delivery, the Guarantor and the
Trust will not offer, sell, contract to sell or otherwise dispose of any
Securities, any security convertible into or exchangeable into or exercisable
for Securities or Subordinated Debentures or any debt securities substantially
similar to the Subordinated Debentures or equity securities substantially
similar to the Securities (except for the Subordinated Debentures and the
Securities issued pursuant to this Agreement), without the prior written consent
of the Underwriters.

           (g)  That the Guarantor and the Trust will use best efforts to effect
the listing of the Securities on the New York Stock Exchange; if the Securities
are exchanged for Subordinated Debentures, the Guarantor will use its best
efforts to effect the listing of the Subordinated Debentures on any exchange on
which the Securities are then listed.

       4. Expenses.
          -------- 

          The Guarantor and the Trust jointly and severally covenant and agree
with the several Underwriters that the Guarantor and the Trust will pay or cause
to be paid the following: (i) all expenses in connection with the

                                       10
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preparation, printing and filing of the Registration Statement as originally
filed and of each amendment thereto; (ii) the fees, disbursements and expenses
of the Guarantor's or the Trust's counsel and accountants in connection with the
issue of the Securities and all other expenses in connection with the
preparation, printing and filing of the Registration Statement, the Prospectus,
the Preliminary Supplemented Prospectus, the Final Supplemented Prospectus and
any amendments and supplements thereto and the mailing and delivering of copies
thereof to the Underwriters and dealers; (iii) all reasonable expenses in
connection with the qualification of the Securities, the Guarantees and the
Subordinated Debentures issuable upon exchange of the Securities, for offering
and sale under state securities laws as provided in Section 3(d) hereof,
including the reasonable fees and disbursements of counsel for the Underwriters
in connection with such qualification and in connection with the Blue Sky and
legal investment surveys; (iv) any fees charged by securities rating services
for rating the Securities and the Subordinated Debentures; (v) the cost of
preparing the Securities and the Subordinated Debentures; (vi) the fees and
expenses of the Trustees, the Guarantee Trustee and the Debenture Trustee and
any agent of the Trustees, the Guarantee Trustee and the Debenture Trustee and
the fees and disbursements of counsel for the Trustees in connection with the
Trust Agreement and the Securities, counsel for the Guarantee Trustee in
connection with the Guarantee and counsel for the Debenture Trustee in
connection with the Indenture and the Subordinated Debentures; (vii) the fees
and disbursements of Delaware counsel to the Trust; (viii) the fees and expenses
incurred in connection with the listing of the Securities and, if applicable,
the Subordinated Debentures on the New York Stock Exchange; and (ix) all other
costs and expenses incident to the performance of its obligations hereunder
which are not otherwise specifically provided for in this Section.  It is
understood, however, that, except as provided in this Section, and Sections 6
and 9 hereof, the Underwriters will pay all of their own costs and expenses,
including the fees of their counsel and any advertising expenses connected with
any offers they may make.

       5.  Conditions of Underwriters' Obligations.
           ---------------------------------------- 

           The obligations of the Underwriter hereunder shall be subject to the
accuracy, at and (except as otherwise stated herein) as of the date hereof and
at and as of the Time of Delivery, of the representations and warranties made
herein by the Guarantor and the Trust, to compliance at and as of the Time of
Delivery by the Guarantor and the Trust with their covenants and agreements
herein contained and the other provisions hereof to be satisfied at or prior to
the

                                       11
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Time of Delivery, and to the following additional conditions:

           (a) (i)  No stop order suspending the effectiveness of the
Registration Statement shall be in effect, and no proceeding for such purpose
shall be pending before or threatened by the Commission, and the Underwriters
shall have received on and as of the Time of Delivery, a certificate dated such
date, signed by an executive officer of the Guarantor or an authorized agent of
the Guarantor designated as such by the Board of Directors of the Guarantor to
the foregoing effect, and (ii) there shall have been no material adverse change
in or affecting the business, properties or financial condition of the Guarantor
or the Trust from that set forth in or contemplated by the Registration
Statement at the time it became effective, except as set forth in or
contemplated by the Prospectus, and the Underwriters shall have received on and
as of the Time of Delivery, a certificate dated such date, signed by an
executive officer of the Guarantor or an executive officer of Houston Industries
Incorporated ("Houston Industries") to the foregoing effect. The officers or
agents making such certificates may rely upon the best of his knowledge as to
proceedings pending or threatened.

           (b) Dewey Ballantine, counsel for the Underwriters, shall have
furnished to you such opinion or opinions, dated the Time of Delivery, with
respect to such matters as you may reasonably request, and such counsel shall
have received such papers and information as they may reasonably request to
enable them to pass upon such matters.  In giving such opinion, such counsel may
rely (i) as to matters of Texas law and the exemption of Houston Industries
under the 1935 Act (as defined herein) upon the opinions of Baker & Botts,
L.L.P. referred to in (d) below and Hugh Rice Kelly or such other counsel
referred to in (c) below and (ii) as to matters of Delaware law upon the opinion
of Richards, Layton & Finger referred to in (e) below.

           (c) Hugh Rice Kelly, Executive Vice President, General Counsel, and
Corporate Secretary for the Guarantor, shall have furnished to you his written
opinion, dated the Time of Delivery, in form and substance satisfactory to you,
to the effect that:

               (i) The Guarantor has been duly incorporated and is validly
existing in good standing under the laws of the State of Texas and has corporate
power and authority to enter into and perform its obligations under this
Agreement and the Guarantor Agreements;

               (ii) No consent, approval, authorization or other order of, or
registration with, any governmental

                                       12
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regulatory body (other than such as may be required under applicable securities
laws, as to which such counsel need not express an opinion) is required for the
issuance and sale of the Securities being delivered at the Time of Delivery or
the issuance of the Guarantee and the Subordinated Debentures or the
consummation by the Trust or the Guarantor of the transactions contemplated by
this Agreement and the Guarantor Agreements;

               (iii) To the best of such counsel's knowledge and other than as
set forth or contemplated in the Prospectus, there are no legal or governmental
proceedings pending or threatened to which Guarantor is subject, which,
individually or in the aggregate, are expected to have a material adverse effect
on the financial position, shareholders' equity or results of operations of the
Guarantor;

               (iv) The issuance by the Guarantor of the Guarantee and the
Subordinated Debentures and the execution, delivery and performance by the
Guarantor of this Agreement and the Guarantor Agreements will not result in the
breach or violation of, or constitute a default under, the Restated Articles of
Incorporation or the Amended and Restated Bylaws of the Guarantor, each as
amended to date, any indenture, mortgage, deed of trust or other agreement or
instrument for borrowed money to which the Guarantor is a party or by which it
is bound or to which its property is subject or any law, order, rule or
regulation of any court or governmental agency or body having jurisdiction over
the Guarantor or its property, in any manner which would have a material adverse
effect on the business of the Guarantor; and

               (v) The description of statutes and regulations set forth in Part
I of the Guarantor's Annual Report on Form 10-K for the fiscal year ended
December 31, 1995 under the captions "Business--Regulatory Matters--Rates and
Services" and "--Environmental Quality" fairly describe in all material
respects the portions of the statutes and regulations addressed thereby.

           (d) Baker & Botts, L.L.P., counsel for the Guarantor and the Trust,
shall have furnished to you their written opinion, dated the Time of Delivery,
in form and substance satisfactory to you, to the effect that:

               (i) Such counsel does not know of any contracts or documents of a
character required to be described in the Registration Statement or Prospectus
or to be filed as exhibits to the Registration Statement which are not so
described and filed;

                                       13
<PAGE>
 
               (ii) The statements set forth in the Final Supplemented
Prospectus under the captions "Certain Terms of Series A Preferred Securities",
"Certain Terms of Series A Subordinated Debentures", "Certain Terms of Series A
Guarantee" and in the Basic Prospectus under the captions "Description of
Securities", "Description of Junior Subordinated Debentures", "Description of
Guarantees" and "Relationship Among the Securities, the Corresponding Junior
Subordinated Debentures, the Expense Agreement and the Guarantees", accurately
summarize in all material respects the terms of the Securities, the Trust
Agreement, the Subordinated Debentures, the Expense Agreement and the Guarantee;

               (iii) The Securities, the Subordinated Debentures and the
Guarantee conform as to legal matters in all material respects to the
descriptions thereof contained in the Final Supplemented Prospectus, including,
without limitation, under the captions "Certain Terms of Series A Preferred
Securities", "Certain Terms of Series A Subordinated Debentures", and "Certain
Terms of Series A Guarantee" and in the Basic Prospectus under the captions
"Description of Junior Subordinated Debentures", "Description of Securities",
"Description of Guarantees", and "Relationship Among the Securities, the
Corresponding Junior Subordinated Debentures, the Expense Agreement and the
Guarantees", respectively;

               (iv) The Subordinated Debentures are in the form prescribed in or
pursuant to the Indenture, have been duly and validly authorized by all
necessary corporate action on the part of the Guarantor and, when executed and
delivered by the Guarantor and authenticated by the Debenture Trustee as
specified in or pursuant to the Indenture, will be valid and binding obligations
of the Guarantor, enforceable in accordance with their terms, except as such
enforceability is subject to the effect of any applicable bankruptcy,
insolvency, reorganization or other law relating to or affecting creditors'
rights generally and to general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law); the Guarantee
has been duly and validly authorized by all necessary corporate action on the
part of the Guarantor; the Guarantee has been duly and validly executed and
delivered by the Guarantor and (assuming due authorization, execution and
delivery by the Trustee thereunder) constitutes the valid and binding obligation
of the Guarantor, enforceable in accordance with its terms, except as such
enforceability is subject to the effect of any applicable bankruptcy,
insolvency, reorganization or other law relating to or affecting creditors'
rights generally and to general principles of equity (regardless of whether such
enforceability is considered in a proceeding in

                                       14
<PAGE>
 
equity or at law); the Trust Agreement, the Indenture and the Expense Agreement
have each been duly authorized, executed and delivered by the Guarantor and,
when executed and delivered by the other parties thereto, will constitute valid
and binding obligations of the Guarantor, enforceable in accordance with their
respective terms, except as such enforceability is subject to the effect of any
applicable bankruptcy, insolvency, reorganization or other law relating to or
affecting creditors' rights generally and to general principles of equity
(regardless of whether such enforceability is considered in proceeding in equity
or at law);

               (v) The Guarantee, the Trust Agreement and the Indenture have
been duly qualified under the TIA;

               (vi) Based upon the timely filing by Houston Industries
Incorporated, a Texas corporation ("Houston Industries"), with the Commission of
an exemption statement pursuant to Rule 2 under the Public Utility Holding
Company Act of 1935 ("1935 Act") which, to the best of the knowledge of such
counsel, is not the subject of any notification provided for in Rule 6 under the
1935 Act, Houston Industries is exempt from the provisions of the 1935 Act
except Sections 9(a)(2), 32 and 33 thereof;

               (vii) The Trust is not and, after giving effect to the offering
and sale of the Securities, will not be an "investment company" or an entity
"controlled" by an "investment company", as such terms are defined in the
Investment Company Act (in giving such opinion counsel may reference specified
"no-action" letters);

               (viii) The Registration Statement has become effective under the
Act, and, to the best of such counsel's knowledge, no stop order suspending the
effectiveness of the Registration Statement or any part thereof has been issued
and no proceedings for that purpose have been instituted and are pending or are
threatened by the Commission under the Act; the Registration Statement, as of
its effective date, and the Final Supplemented Prospectus, as of January 30,
1997, (except for (A) the operating statistics, financial statements and
financial statement schedules contained or incorporated by reference therein or
omitted therefrom (including the auditors' reports on the financial statements
and the notes to the financial statements), (B) the other financial and
statistical information contained or incorporated by reference therein or
omitted therefrom and (C) the exhibits thereto, as to which such counsel need
not express an opinion) complied as to form in all material respects with the
requirements of Form S-3 under the Act and the applicable rules and regulations
of the Commission thereunder, and each document incorporated by reference

                                       15
<PAGE>
 
therein as originally filed pursuant to the Exchange Act (except for (A) the
operating statistics, financial statements and financial statement schedules
contained or incorporated by reference therein or omitted therefrom (including
the auditors' reports on the financial statements and the notes to the financial
statements), (B) the other financial and statistical information contained or
incorporated by reference therein or omitted therefrom and (C) the exhibits
thereto, as to which such counsel need not express an opinion) when so filed
complied as to form in all material respects with the Exchange Act and the
applicable rules and regulations of the Commission thereunder; and

               (ix) The execution, delivery and performance by the Guarantor of
this Agreement have been duly authorized by all necessary corporate action on
the part of the Guarantor, and this Agreement has been duly executed and
delivered by the Guarantor.

           In addition, such counsel shall state that no facts have come to the
attention of such counsel that lead them to believe that the Registration
Statement (except for (A) the operating statistics, financial statements and
financial statement schedules contained or incorporated by reference therein
(including the auditors' reports on the financial statements and the notes to
the financial statements, except to the extent that such notes describe legal or
governmental proceedings to which the Company is a party and are incorporated by
reference into one or more items of a report that is incorporated by reference
in the Registration Statement or the Prospectus, other than an item that
requires that financial statements be provided), (B) the other financial and
statistical information contained or incorporated by reference therein and (C)
the exhibits thereto, as to which such counsel need not comment) as of the time
such Registration Statement became effective, contained any untrue statement of
a material fact or omitted to state a material fact required to be stated
therein or necessary to make the statements therein not misleading, or that the
Prospectus, as amended, supplemented or modified by the filing of a document
incorporated by reference therein if so amended, supplemented or modified
(except for (A) the operating statistics, financial statement and financial
statement schedules contained or incorporated by reference therein (including
the auditors' reports on the financial statements and the notes to the financial
statements, except to the extent that such notes describe legal or governmental
proceedings to which the Guarantor is a party and are incorporated by reference
into one or more items of a report that is incorporated by reference in the
Prospectus, other than an item that requires that financial statements be
provided), (B) the other financial and statistical information contained or
incorporated by

                                       16
<PAGE>
 
reference therein and (C) the exhibits thereto, as to which such counsel need
not comment), as of the date of the Final Supplemented Prospectus contained, or
as of the Time of Delivery contains, any untrue statement of a material fact or
omits to state a material fact necessary in order to make the statements
therein, in light of the circumstances under which they were made, not
misleading.

           (e) Richards, Layton & Finger, special Delaware counsel for the
Guarantor and the Trust, shall have furnished to you their written opinion,
dated the Time of Delivery, in form and substance satisfactory to you, to the
effect that:

               (i) The Trust has been duly created and is validly existing in
good standing as a business trust under the Delaware Business Trust Act, and all
filings required under the laws of the State of Delaware with respect to the
creation and valid existence of the Trust as a business trust have been made;

               (ii) Under the Delaware Business Trust Act and the Trust
Agreement, the Trust has the trust power and authority to own property and
conduct its business, all as described in the Prospectus;

               (iii) The Trust Agreement constitutes a valid and legally binding
obligation of the Guarantor and the Trustees, and is enforceable against the
Guarantor and the Trustees, in accordance with its terms, subject, as to
enforcement, to the effect upon the Trust Agreement of (i) bankruptcy,
insolvency, fraudulent transfer and conveyance, reorganization, moratorium,
receivership, liquidation and other similar laws relating to or affecting the
rights and remedies of creditors generally, (ii) principles of equity, including
applicable law relating to fiduciary duties (regardless of whether considered
and applied in a proceeding in equity or at law), and (iii) the effect of
applicable public policy on the enforceability of provisions relating to
indemnification or contribution;

               (iv) Under the Delaware Business Trust Act, the Original Trust
Agreement (as defined in the Trust Agreement) and the Trust Agreement, the Trust
has the trust power and authority to (a) execute and deliver, and to perform its
obligations under this Agreement and (b) issue and perform its obligations under
the Securities and the Common Securities;

               (v) Under the Delaware Business Trust Act, the Original Trust
Agreement and the Trust Agreement, the execution and delivery by the Trust of
this Agreement, and

                                       17
<PAGE>
 
the performance by the Trust of its obligations hereunder, have been duly
authorized by all necessary trust action on the part of the Trust;

               (vi) Under the Delaware Business Trust Act,the Original Trust
Agreement and the Trust Agreement, the Agreement has been duly executed by the
Trust;

               (vii) The Securities have been duly authorized by the Trust
Agreement and are duly and validly issued and, subject to the qualifications set
forth herein, fully paid and non-assessable undivided beneficial interests in
the assets of the Trust and are entitled to the benefits provided by the Trust
Agreement (subject to the terms of the Trust Agreement); provided that such
counsel may note that the Securityholders may be obligated, pursuant to the
Trust Agreement, to (a) provide indemnity and/or security in connection with and
pay taxes or governmental charges arising from transfers or exchanges of Capital
Securities Certificates and the issuance of replacement Capital Securities
Certificates and (b) provide security and indemnity in connection with requests
of or directions to the Property Trustee (as defined in the Trust Agreement) to
exercise its rights and remedies under the Trust Agreement. The Securityholders,
as beneficial owners of the Trust, are entitled to the same limitation of
personal liability extended to stockholders of private corporations for profit
organized under the General Corporation Law of the State of Delaware;

               (viii) The Common Securities of the Trust have been duly
authorized by the Trust Agreement and are validly issued and fully paid
undivided beneficial interests in the assets of the Trust;

               (ix) Under the Delaware Business Trust Act and the Trust
Agreement, the issuance of the Securities and the Common Securities is not
subject to preemptive rights;

               (x) The issuance and sale by the Trust of the Securities and the
Common Securities, the execution, delivery and performance by the Trust of this
Agreement, the consummation by the Trust of the transactions contemplated by
this Agreement and the Trust Agreement and compliance by the Trust with its
obligations thereunder do not violate (a) any of the provisions of the
Certificate of Trust of the Trust or the Trust Agreement, or (b) any applicable
Delaware law or administrative regulation;

               (xi) Such counsel has reviewed the statements in the Basic
Prospectus under the caption "The Issuers" and the statements in the Preliminary
Supplemented Prospectus and Final Supplemented Prospectus under the caption
"HL&P

                                       18
<PAGE>
 
Capital Trust I" and, insofar as they contain statements of Delaware law, such
statements are fairly presented;

               (xii) No authorization, approval, consent or order of any
Delaware court or Delaware governmental authority or Delaware agency is required
to be obtained by the Trust solely in connection with the issuance and sale of
the Securities and the Common Securities. (In rendering the opinion expressed in
this paragraph (xii), such counsel need express no opinion concerning the
securities laws of the State of Delaware.); and

               (xiii) Assuming that (i) the Trust derives no income from or
connected with sources within the State of Delaware and has no assets,
activities (other than maintaining the Delaware Trustee and the filing of
documents with the Secretary of State of the State of Delaware) or employees in
the State of Delaware, and (ii) the Trust is treated as a grantor trust for
federal income tax purposes, the Securityholders (other than those holders of
the Securities who reside or are domiciled in the State of Delaware) will have
no liability for income taxes imposed by the State of Delaware solely as a
result of their participation in the Trust, and the Trust will not be liable for
any income tax imposed by the State of Delaware.

           (f) Baker & Botts, L.L.P., special tax counsel for the Guarantor and
the Trust, shall have furnished to you their written opinion, dated the Time of
Delivery, in form and substance satisfactory to you, to the effect that such
firm confirms its opinion set forth in the Final Supplemented Prospectus under
the caption "Certain Federal Income Tax Consequences".

           (g) At the time of execution of this Agreement, Deloitte & Touche LLP
shall have furnished to you a letter dated the date of such execution,
substantially in the form heretofore supplied and deemed satisfactory to you.

           (h) At the Time of Delivery, Deloitte & Touche LLP shall have
furnished you a letter, dated the Time of Delivery, to the effect that such
accountants reaffirm, as of the Time of Delivery and as though made on the Time
of Delivery, the statements made in the letter furnished by such accountants
pursuant to paragraph (g) of this Section 5, except that the specified date
referred to in such letter will be a date not more than five business days prior
to the Time of Delivery.

           (i) A Special Event (as defined in the Final Supplemented Prospectus,
except that the reference to effectiveness or announcement on or after the date
of issuance of the Securities shall be deemed a reference to

                                       19
<PAGE>
 
effectiveness or announcement on or after the date of this Agreement) shall not
have occurred and be continuing.

           (j) The Guarantor and the Trust shall have furnished or caused to be
furnished to you at the Time of Delivery certificates of officers of the
Guarantor or an authorized agent of the Guarantor designated as such by the
Board of Directors of the Guarantor and of administrators of the Trust
satisfactory to you as to the accuracy of the representations and warranties of
the Guarantor and the Trust herein at and as of the Time of Delivery, as to the
performance by the Guarantor and the Trust of all of their respective
obligations hereunder to be performed at or prior to the Time of Delivery, as to
the matters set forth in the introductory paragraph to this Section 5 and
subsection (a) of this Section and as to such other matters as you may
reasonably request.

        6. Indemnification and Contribution.
           --------------------------------- 

           (a) The Guarantor and the Trust, jointly and severally, agree to
indemnify and hold harmless each Underwriter, and each person, if any, who
controls each Underwriter within the meaning of the Act or the Exchange Act,
against any losses, claims, damages, liabilities or expenses (including the
reasonable cost of investigating and defending against any claims therefore and
counsel fees incurred in connection therewith), joint or several, which may be
based upon either the Act, or the Exchange Act, or any other statute or at
common law, on the ground or alleged ground that any Preliminary Supplemented
Prospectus, Final Supplemented Prospectus, Preliminary Prospectus, the
Registration Statement, the Basic Prospectus or the Prospectus (or any such
document, as from time to time amended, or deemed to be amended, supplemented or
modified) includes or allegedly includes an untrue statement of material fact or
omits to state a material fact required to be stated therein or necessary in
order to make the statements therein not misleading, unless such statement or
omission was made in reliance upon, and in conformity with, written information
furnished to the Guarantor or the Trust by any Underwriter through Goldman,
Sachs & Co. specifically for use in the preparation thereof; provided that in no
case is the Guarantor or the Trust to be liable with respect to any claims made
against any Underwriter or any such controlling person unless such Underwriter
or such controlling person shall have notified the Guarantor in writing within a
reasonable time after the summons or other first legal process giving
information of the nature of the claim shall have been served upon such
Underwriter or such controlling person, but failure to notify the Guarantor or
Trust of any such claim shall not relieve it from any liability which it may
have to such Underwriter or such

                                       20
<PAGE>
 
controlling person otherwise than on account of the indemnity agreement
contained in this paragraph; and provided, further, that the foregoing indemnity
with respect to the Preliminary Prospectus, the Basic Prospectus, the
Prospectus, the Preliminary Supplemented Prospectus and the Final Supplemented
Prospectus shall not inure to the benefit of any Underwriter if a copy of the
Preliminary Prospectus, the Basic Prospectus, the Prospectus, the Preliminary
Supplemented Prospectus or the Final Supplemented Prospectus as amended or
supplemented, had not been sent or given by or on behalf of such Underwriter to
the person asserting any such losses, claims, damages or liabilities
concurrently with or prior to delivery of the written confirmation of the sale
of Securities to such person and the untrue statement or omission of a material
fact contained in any such Preliminary Prospectus, Basic Prospectus, Prospectus,
Preliminary Supplemented Prospectus or Final Supplemented Prospectus was
corrected in the Preliminary Prospectus, Basic Prospectus, Prospectus,
Preliminary Supplemented Prospectus or Final Supplemented Prospectus, as amended
or supplemented.

           The Guarantor and the Trust will be entitled to participate at their
own expense in the defense, or, if they so elect, to assume the defense of any
suit brought to enforce any such liability, but, if the Guarantor or the Trust
elects to assume the defense, such defense shall be conducted by counsel chosen
by it. In the event that the Guarantor or the Trust elects to assume the defense
of any such suit and retains such counsel, the Underwriter or Underwriters or
controlling person or persons, defendant or defendants in the suit, may retain
additional counsel but shall bear the fees and expenses of such counsel unless
(i) the Guarantor or the Trust shall have specifically authorized the retaining
of such counsel or (ii) the parties to such suit include the Underwriter or
Underwriters or controlling person or persons and the Underwriter or
Underwriters or controlling person or persons have been advised by such counsel
that one or more legal defenses may be available to it or them which may not be
available to the Guarantor or the Trust, in which case the Guarantor or the
Trust shall not be entitled to assume the defense of such suit on behalf of such
Underwriter or Underwriters or controlling person or persons, notwithstanding
their obligation to bear the reasonable fees and expenses of such counsel, it
being understood, however, that the Guarantor and the Trust shall not, in
connection with any one such suit or proceeding or separate but substantially
similar or related actions or proceedings in the same jurisdiction arising out
of the same general allegations or circumstances, be liable for the reasonable
fees and expenses of more than one separate firm of attorneys at any

                                       21
<PAGE>
 
time for all such Underwriters and their controlling persons, which firm shall
be designated in writing by Goldman, Sachs & Co.  The Guarantor and the Trust
shall not be liable to indemnify any person for any settlement of any such claim
effected without the Guarantor's or the Trust's consent.  This indemnity
agreement will be in addition to any liability which the Guarantor and the Trust
might otherwise have.

           (b) Each Underwriter agrees to indemnify and hold harmless the
Guarantor and the Trust, each of the Guarantor's directors, each of the
Guarantor's officers who have signed the Registration Statement, each of the
Trustees who have signed the Registration Statement and each person, if any, who
controls the Guarantor and the Trust within the meaning of the Act or the
Exchange Act, against any losses, claims, damages, liabilities or expenses
(including the reasonable cost of investigating and defending against any claims
therefor and counsel fees incurred in connection therewith), joint or several,
which may be based upon the Act, or any other statute or at common law, on the
ground or alleged ground that any Preliminary Supplemented Prospectus, Final
Supplemented Prospectus, Preliminary Prospectus, the Registration Statement, the
Basic Prospectus or the Prospectus (or any such document, as from time to time
amended, or deemed to be amended, supplemented or modified) includes or
allegedly includes an untrue statement of a material fact or omits to state a
material fact required to be stated therein or necessary in order to make the
statements therein not misleading, but only insofar as any such statement or
omission was made in reliance upon, and in conformity with, written information
furnished to the Guarantor or the Trust by such Underwriter through Goldman
Sachs & Co. specifically for use in the preparation thereof; provided that in no
case is such Underwriter to be liable with respect to any claims made against
the Guarantor or the Trust or any such director, officer, trustee or controlling
person unless the Guarantor or the Trust or any such director, officer, trustee
or controlling person shall have notified such Underwriter in writing within a
reasonable time after the summons or other first legal process giving
information of the nature of the claim shall have been served upon the Guarantor
or the Trust or any such director, officer, trustee or controlling person, but
failure to notify such Underwriter of any such claim shall not relieve it from
any liability which it may have to the Guarantor or the Trust or any such
director, officer, trustee or controlling person otherwise than on account of
the indemnity agreement contained in this paragraph. Such Underwriter will be
entitled to participate at its own expense in the defense, or, if it so elects,
to assume the defense of any suit brought to enforce any such liability, but, if
such Underwriter elects to assume the defense, such

                                       22
<PAGE>
 
defense shall be conducted by counsel chosen by it. In the event that such
Underwriter elects to assume the defense of any such suit and retain such
counsel, the Guarantor or the Trust or such director, officer, trustee or
controlling person, defendant or defendants in the suit, may retain additional
counsel but shall bear the fees and expenses of such counsel unless (i) such
Underwriter shall have specifically authorized the retaining of such counsel or
(ii) the parties to such suit include the Guarantor or the Trust or any such
director, officer, trustee or controlling person and such Underwriter and the
Guarantor or the Trust or such director, officer, trustee or controlling person
have been advised by such counsel that one or more legal defenses may be
available to it or them which may not be available to such Underwriter, in which
case such Underwriter shall not be entitled to assume the defense of such suit
on behalf of the Guarantor or the Trust or such director, officer, trustee or
controlling person, notwithstanding its obligation to bear the reasonable fees
and expenses of such counsel, it being understood, however, that such
Underwriter shall not, in connection with any one such suit or proceeding or
separate but substantially similar or related actions or proceedings in the same
jurisdiction arising out of the same general allegations or circumstances, be
liable for the reasonable fees and expenses of more than one separate firm of
attorneys at any time for all of the Guarantor or the Trust and any such
director, officer, trustee or controlling person, which firm shall be designated
in writing by the Guarantor. Such Underwriter shall not be liable to indemnify
any person for any settlement of any such claim effected without such
Underwriter's consent. This indemnity agreement will be in addition to any
liability which such Underwriter might otherwise have.

           (c) If recovery is not available under Section 6(a) or 6(b) hereof,
for any reason other than as specified therein, the parties entitled to
indemnification by the terms thereof shall be entitled to contribution for
liabilities and expenses, except to the extent that contribution is not
permitted under Section 11(f) of the Act.  In determining the amount of
contribution to which the respective parties are entitled, there shall be
considered the relative benefits received by each party from the offering of the
Securities (taking into account the portion of the proceeds of the offering
realized by each), the parties' relative knowledge and access to information
concerning the matter with respect to which the claim was asserted, the
opportunity to correct and prevent any statement or omission, and any other
equitable considerations appropriate under the circumstances.  The Guarantor and
the Trust and the Underwriters agree that it would not be equitable if the
amount of such contribution

                                       23
<PAGE>
 
were determined by pro rata or per capita allocation (even if the Underwriters
were treated as one entity for such purpose).  No Underwriters or any person
controlling such Underwriters shall be obligated to make contribution hereunder
which in the aggregate exceeds the total public offering price of the Securities
purchased by such Underwriters under this Agreement, less the aggregate amount
of any damages which such Underwriters and its controlling persons have
otherwise been required to pay in respect of the same claim or any substantially
similar claim. The Underwriters' obligations to contribute are several in
proportion to their respective underwriting obligations, and not joint.

         7. Substitution of Underwriters.
            ----------------------------- 

            If any Underwriter shall default in its obligation to purchase the
Securities which it has agreed to purchase hereunder and the aggregate principal
amount of such Securities which such defaulting Underwriter agreed but failed to
purchase does not exceed 10% of the aggregate principal amount of all the
Securities, the non-defaulting Underwriters may make arrangements satisfactory
to the Guarantor and Trust for the purchase of the aggregate principal amount of
such Securities by other persons, including the non-defaulting Underwriters, but
if no such arrangements are made prior to the Time of Delivery, the non-
defaulting Underwriters shall be obligated severally in proportion to their
respective commitments hereunder, to purchase the Securities which such
defaulting Underwriter agreed but failed to purchase. If any Underwriter or
Underwriters shall so default and the aggregate principal amount of such
Securities with respect to which such default or defaults occur is more than 10%
of the aggregate principal amount of all the Securities and arrangements
satisfactory to the non-defaulting Underwriters and the Guarantor and the Trust
for the purchase of such Securities by other persons are not made within 48
hours after such default, this agreement will terminate.

           If the non-defaulting Underwriter or substituted underwriter or
underwriters are required hereby or agree to take up all or part of the
Securities of the defaulting Underwriter as provided in this Section 7, (i) the
Guarantor and the Trust shall have the right to postpone the Time of Delivery
for a period of not more than five full business days, in order that the
Guarantor and the Trust may effect whatever changes may thereby be made
necessary in the Registration Statement or Prospectus or in any other documents
or arrangements, and the Guarantor and the Trust agree to promptly file any
amendments to the Registration Statement or supplements to the Prospectus which
may thereby be made necessary, and (ii) the respective aggregate

                                       24
<PAGE>
 
principal amount of Securities which the non-defaulting Underwriters or
substituted purchaser or purchasers shall thereafter be obligated to purchase
shall be taken as the basis of their underwriting obligation for all purposes of
this Agreement.  Nothing herein contained shall relieve any defaulting
Underwriter of its liability to the Guarantor and the Trust or the non-
defaulting Underwriters for damages occasioned by its default hereunder.  Any
termination of this Agreement pursuant to this Section 7 shall be without
liability on the part of the non-defaulting Underwriters or the Guarantor or the
Trust, other than as provided in Sections 6 and 9.

        8. Survival of Indemnities, Representations, Warranties, etc.
           ----------------------------------------------------------

           The respective indemnities, agreements, representations, warranties
and other statements of the Guarantor and the Trust and the several
Underwriters, as set forth in this Agreement or made by or on behalf of them,
respectively, pursuant to this Agreement, shall remain in full force and effect,
regardless of any investigation (or any statement as to the results thereof)
made by or on behalf of any Underwriter or any controlling person of any
Underwriter, or the Guarantor or the Trust, or any officer or director or
controlling person of the Guarantor or the Trust, and shall survive delivery of
and payment for the Securities.

        9. Termination.
           ----------- 

           If this Agreement shall be terminated by the Underwriters, because of
any failure or refusal on the part of the Guarantor or the Trust to comply with
the terms or to fulfill any of the conditions of this Agreement, or if for any
reason the Guarantor or the Trust shall be unable to perform its obligations
under this Agreement, the respective indemnities shall remain in full force and
effect and the Guarantor or the Trust will reimburse the Underwriter or such
Underwriters as have so terminated this Agreement with respect to themselves for
all out-of-pocket expenses (including the fees and disbursements of their
counsel) reasonably incurred by them in connection with the transactions
contemplated by this Agreement.

       10. Notices.
           ------- 

           In all dealings hereunder, you shall act on behalf of each of the
Underwriters, and the parties hereto shall be entitled to act and rely upon any
statement, request, notice or agreement on behalf of any Underwriter made or
given by you.

                                       25
<PAGE>
 
           All statements, requests, notices and agreements hereunder shall be
in writing, and (i) if to the Underwriters shall be delivered or sent by mail,
telex or facsimile transmission to you in care of Goldman, Sachs & Co., 85 Broad
Street, New York, New York 10004, Attention: Registration Department; (ii) if to
the Guarantor shall be delivered or sent by mail, telex or facsimile
transmission to the Guarantor in care of Houston Industries Incorporated, 1111
Louisiana, Houston, Texas 77002, Attention, Assistant Treasurer; and (iii) if to
the Trust shall be delivered or sent by mail, telex or facsimile transmission to
the Trust, 200 West 9th Street Plaza, Box 2105, Wilmington, Delaware 19899.  Any
such statements, requests, notices or agreements shall take effect upon receipt
thereof.

       11. Successors.
           ---------- 

           This Agreement shall inure to the benefit of and be binding upon the
several Underwriters, the Guarantor and the Trust and their respective
successors and the directors, trustees, officers and controlling persons
referred to in Section 6 of this Agreement.  Nothing expressed or mentioned in
this Agreement is intended or shall be construed to give any person other than
the persons mentioned in the preceding sentence any legal or equitable right,
remedy or claim under or in respect of this Agreement, or any provisions herein
contained; this Agreement and all conditions and provisions hereof being
intended to be, and being, for the sole and exclusive benefit of such persons
and for the benefit of no other person; except that the representations,
warranties, covenants, agreements and indemnities of the Guarantor and the Trust
contained in this Agreement shall also be for the benefit of the person or
persons, if any, who control any Underwriter within the meaning of the Act or
the Exchange Act, and the representations, warranties, covenants, agreements and
indemnities of the several Underwriters shall also be for the benefit of each
Trustee, each director of the Guarantor, each person who has signed the
Registration Statement and the person or persons, if any, who control the
Guarantor and the Trust within the meaning of the Act.

       12. Applicable Law.
           -------------- 

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

       13. Counterparts.
           ------------ 

           This Agreement may be executed by any one or more  of the parties
hereto in any number of counterparts, each of which shall be deemed to be an
original, but all such respective counterparts shall together constitute one and
the same instrument.

                                       26
<PAGE>
 
           If the foregoing is in accordance with your understanding, please
sign and return to us seven counterparts hereof, and upon the acceptance hereof
by you, on behalf of each of the Underwriters, this letter and such acceptance
hereof shall constitute a binding agreement between each of the Underwriters and
the Guarantor and the Trust. It is understood that your acceptance of this
letter on behalf of each of the Underwriters is pursuant to the authority set
forth in a form of Agreement among Underwriters, the form of which shall be
submitted to the Guarantor and the Trust for examination upon request, but
without warranty on your part as to the authority of the signers thereof.

                                       27
<PAGE>
 
                                   Very truly yours,


                                   HL&P Capital Trust I
                                   By: Houston Lighting & Power Company,
                                        as Depositor



                                   By: /s/ LINDA GEIGER
                                      -------------------------------
                                      Name: Linda Geiger
                                      Title: Authorized Agent


                                   Houston Lighting & Power Company



                                   By: /s/ LINDA GEIGER
                                      -------------------------------
                                      Name: Linda Geiger
                                      Title: Authorized Agent


                
Accepted as of the date hereof:
Goldman, Sachs & Co.
Merrill Lynch, Pierce, Fenner
  & Smith Incorporated
Dean Witter Reynolds Inc.
Donaldson, Lufkin & Jenrette
  Securities Corporation
A.G. Edwards & Sons, Inc.
PaineWebber Incorporated
Prudential Securities Incorporated
Smith Barney Inc.


By: /s/ GOLDMAN, SACHS & CO.
   ---------------------------
      (Goldman, Sachs & Co.)

     On behalf of each of the Underwriters

                                       28
<PAGE>
 
                             SCHEDULE I
 
 
                                            Number of
                                            Securities
                                              to be
Underwriters                                Purchased
------------------------------------------  ----------
Goldman, Sachs & Co. .....................     919,000
Merrill Lynch, Pierce, Fenner &
 Smith Incorporated.......................     919,000
Dean Witter Reynolds Inc. ................     918,000
Donaldson, Lufkin & Jenrette
 Securities Corporation...................     918,000
A.G. Edwards & Sons, Inc. ................     918,000
PaineWebber Incorporated..................     918,000
Prudential Securities Incorporated........     918,000
Smith Barney Inc. ........................     918,000
 
Bear, Sterns & Co. Inc. ..................     106,000
Alex Brown & Sons Incorporated............     106,000
Credit Suisse First Boston Corporation....     106,000
Dillon, Read & Co. Inc. ..................     106,000
EVEREN Securities, Inc. ..................     106,000
Lehman Brothers Inc. .....................     106,000
Oppenheimer & Co., Inc. ..................     106,000
Principal Financial Securities, Inc. .....     106,000
Rauscher Pierce Refsnes, Inc. ............     106,000
 
Advest, Inc. .............................      50,000
Robert W. Baird & Co. Incorporated........      50,000
J.C. Bradford & Co. ......................      50,000
Cowen & Company...........................      50,000
Crowell, Weedon & Co. ....................      50,000
Dain Bosworth Incorporated................      50,000
Fahnestock & Co. Inc. ....................      50,000
First Albany Corporation..................      50,000
First of Michigan Corporation.............      50,000
First Southwest Company...................      50,000
J.J.B. Hilliard, W.L. Lyons, Inc. ........      50,000
Interstate/Johnson Lane Corporation.......      50,000
Janney Montgomery Scott Inc. .............      50,000
Kennedy, Cabot & Co. .....................      50,000
Legg Mason Wood Walker, Incorporated......      50,000
McDonald & Company Securities, Inc. ......      50,000
McGinn, Smith & Co., Inc. ................      50,000
Morgan Keegan & Company, Inc. ............      50,000
The Ohio Company..........................      50,000
Olde Discount Corporation.................      50,000
Piper Jaffray Inc. .......................      50,000
Raymond James & Associates, Inc. .........      50,000
The Robinson-Humphrey Company, Inc. ......      50,000
 

                                       29
<PAGE>
 
Roney & Co., LLC..........................      50,000
Southwest Securities, Inc. ...............      50,000
Stephens Inc. ............................      50,000
Sterne, Agee & Leach, Inc. ...............      50,000
Stifel, Nicolaus & Company, Incorporated..      50,000
Sutro & Co. Incorporated..................      50,000
Trilon International Inc. ................      50,000
Tucker Anthony Incorporate................      50,000
U.S. Clearing Corp. ......................      50,000
Wedbush Morgan Securities.................      50,000
Wheat, First Securities, Inc. ............      50,000
        
  Total...................................  10,000,000

                                       30