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                                                                     EXHIBIT 1.2


                             HL&P Capital Trust II


                      8.257% Capital Securities, Series B
             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
c/o Goldman, Sachs & Co.
85 Broad Street,
New York, New York 10004

Ladies and Gentlemen:

          HL&P Capital Trust II, 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 I hereto (the
"Underwriters") an aggregate of $100,000,000 liquidation amount of 8.257%
Capital Securities, Series B (liquidation amount $1,000 per capital 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 $3,093,000 liquidation amount of its Common
Securities (liquidation amount $1,000 per common security) (the "Common
Securities") by the Trust are to be invested in Junior Subordinated Debentures,
Series B
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(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.

          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 333-20069-02) 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  Final Supplemented
     Prospectus (hereinafter defined)), is hereinafter referred to as the
     "Prospectus". Any reference herein to the Registration Statement, the
     Prospectus, the Basic 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,
     the Basic Prospectus, or the Final Supplemented Prospectus. Any reference
     herein to the terms "amend", "amendment"

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     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 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; 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 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

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     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 in the Trust Agreement, will be duly and validly
     issued 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 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

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     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, 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 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

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     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

                                       6
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     be required under state securities or Blue Sky laws 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 $10 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 $1,000,000.

     (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, on Tuesday, February 4, 1997 or such other time and date as
Goldman, Sachs & Co.

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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 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 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 respect to documents
     filed pursuant to the Exchange Act and incorporated by reference into the

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     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

                                       9
<PAGE>
 
     incorporated by reference in the Prospectus, which shall be so supplied to
     the Underwriters and such dealers, in either 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.

     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 preparation, printing and
     filing of the Registration Statement as originally filed and of each
     amendment thereto;

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          (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
     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;
     and

          (viii)  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

                                       11
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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 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

                                       12
<PAGE>
 
     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 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

                                       13
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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;

          (ii)  The statements set forth in the Final Supplemented Prospectus
     under the captions "Certain Terms of Series B Capital Securities", "Certain
     Terms of Series B Subordinated Debentures", "Certain Terms of Series B
     Guarantee" and in the Basic Prospectus under the caption "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, and the statements under the caption "ERISA Considerations"
     insofar as they purport to describe the provisions of the laws and
     regulations referred to therein are accurate summaries in all materials
     respects thereof;

          (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 B Capital
     Securities", "Certain Terms of Series B Subordinated Debentures", and
     "Certain Terms of Series B 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

                                       14
<PAGE>
 
     creditors' rights generally and to general principles of equity (regardless
     of whether such enforceability is considered in a proceeding in equity or
     at law);

          (v)  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 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);

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

          (vii)  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;

          (viii)  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);

                                       15
<PAGE>
 
          (ix)  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 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

          (x)  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

                                       16
<PAGE>
 
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 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

                                       17
<PAGE>
 
     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
     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 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, this 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

                                       18
<PAGE>
 
     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 Final
     Supplemented Prospectus under the caption "HL&P Capital Trust II" 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

                                       19
<PAGE>
 
     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 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,

                                       20
<PAGE>
 
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 Final Supplemented 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 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, the Basic Prospectus, the
Prospectus, and the Final Supplemented Prospectus shall not inure to the benefit
of any Underwriter if a copy of the Basic Prospectus, the 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 Basic Prospectus,
Prospectus, or Final Supplemented Prospectus was corrected in the Basic
Prospectus, 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

                                       21
<PAGE>
 
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
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 Final Supplemented 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

                                       22
<PAGE>
 
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 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
any 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 any 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

                                       23
<PAGE>
 
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 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

                                       24
<PAGE>
 
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 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

                                       25
<PAGE>
 
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.

     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.

                                       26
<PAGE>
 
     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.

     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 II

                         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


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

On behalf of each of the Underwriters

                                       28
<PAGE>
 
                                   SCHEDULE I

<TABLE>
<CAPTION>
 
 
                                            Liquidation
                                             Amount of
                                          Securities to be
Underwriters                                 Purchased
------------                                 ---------
<S>                                        <C>
Goldman, Sachs & Co.....................   $ 50,000,000
 
Merrill Lynch, Pierce, Fenner & Smith
        Incorporated....................     50,000,000
                                           ------------
 
Total...................................   $100,000,000
 
</TABLE>

                                       29