Exhibit 5.1

[IP LOGO]

TWO MANHATTANVILLE ROAD
PURCHASE, NY 10577

                         



                                                          September 24, 1998

Securities and Exchange Commission
Judiciary Plaza
450 5th Street, N.W.
Washington, D.C. 20549

                        Re: International Paper Company,
                    International Paper Capital Trust III and
                      International Paper Capital Trust IV
                       Registration Statement on Form S-3

Dear Sirs:

         This opinion is furnished by me as counsel for International Paper
Company, a New York corporation (the "Company"), in connection with the
Registration Statement on Form S-3 filed by the Company with the Securities and
Exchange Commission under the Securities Act of 1933, as amended (the
"Securities Act"). The Registration Statement relates to the issuance and sale
from time to time, of, among other securities, the following securities of the
Company with an aggregate initial public offering price of up to $1,100,000,000
or the equivalent thereof, based on the applicable exchange rate at the time of
sale, in one or more foreign currencies, currency units or composite currencies
as shall be designated by the Company: (i) debt securities (the "Debt
Securities") which may be either senior debt securities (the "Senior Debt
Securities") or subordinated debt securities (the "Subordinated Debt
Securities"); (ii) shares of its serial preferred stock, $1.00 par value (the
"Preferred Stock"), which may also be issued in the form of depositary shares
(the "Depositary Shares") evidenced by depositary receipts



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(the "Receipts"); (iii) shares of its common stock, $1.00 par value (the "Common
Stock"); (iv) warrants to purchase securities of the Company as shall be
designated by the Company at the time of offering (the "Warrants"); (v) such
indeterminate number of shares of Common Stock as may be issued upon conversion
or exchange of any securities, including such shares of Common Stock as may be
issued pursuant to anti-dilution adjustments, in amounts, at prices and on terms
to be determined at the time of offering (the "Indeterminate Securities"); and
(vi) the Guarantee (as defined below) of the Company with respect to certain
Trust Preferred Securities that may be issued by International Paper Capital
Trust III and International Paper Capital Trust IV (each a "Trust") pursuant to
an Amended and Restated Declaration of Trust of each Trust (the "Declaration"),
among the Company, as sponsor and as the issuer of certain debentures to be held
by the Property Trustee (as defined below), The Bank of New York, as Property
Trustee (the "Property Trustee"), The Bank of New York (Delaware), as Delaware
trustee, and the regular trustees named therein. Pursuant to Rule 429 under the
Securities Act, the prospectus included in the Registration Statement also
relates to $2,000,000,000 in aggregate proceeds of securities registered under
Registration Statement No. 33-52945 and $400,000,000 in aggregate proceeds of
securities registered as Debt Securities under Registration Statement No.
33-48167 (such $2,400,000,000 of securities collectively referred to as the
"Registered Securities" and the two registration statements collectively, the
"Prior Registration Statements"). The Debt Securities, Preferred Stock, Common
Stock, Warrants, Indeterminate Securities, Registered Securities and Guarantee
are collectively referred to herein as the "Securities." The Senior Debt
Securities may be issued under an Indenture (the "Senior Indenture") proposed to
be entered into between the Company and The Chase Manhattan Bank, N.A. or
another trustee (the "Senior Indenture Trustee"). The Subordinated Debt
Securities may be issued under a separate Indenture (the "Subordinated
Indenture" and, together with the Senior Indenture, the "Indentures"), proposed
to be entered into between the Company and The Chase Manhattan Bank, N.A., or
another trustee (the "Subordinated Indenture Trustee" and, together with the
Senior Indenture Trustee, the "Trustees").

         This opinion is delivered in accordance with the requirements of Items
601(b) (5) of Regulation S-K under the Securities Act.

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         I have examined and am familiar with originals or copies of such
documents, corporate records and other instruments as I have deemed necessary or
appropriate in connection with this opinion, including (i) the form of
Registration Statement relating to, among other securities the Securities; (ii)
the Prior Registration Statements; (iii) the form of the Senior Indenture; (iv)
the form of the Subordinated Indenture; (v) the forms of underwriting agreements
(including the Underwriting Agreement Standard Provisions relating to firm
commitment underwritten offerings of Debt Securities, Preferred Stock and Common
Stock, respectively, incorporated therein) that may be entered into between the
Company and one or more underwriters named therein in connection with any
offering of the Securities (the "Underwriting Agreements"); (vi) the form of
deposit agreement (the "Deposit Agreement") that may be entered into among the
Company, a depositary to be appointed by the Company (the "Depositary"), and the
holders from time to time of Receipts issued thereunder in connection with any
offering of Depositary Shares; (vii) the Certificate of Incorporation of the
Company, as amended; (viii) the By-laws of the Company as currently in effect;
(ix) resolutions adopted to date by the Board of Directors of the Company (the
"Board") relating to the issuance of the Securities (the "Board Resolutions");
and (x) the form of the Guarantee Agreement (the "Guarantee") between the
Company, as guarantor, and The Bank of New York, as guarantee trustee, for the
benefit of the holders of the Trust Preferred Securities of each Trust.

         I am a member of the Bar of the State of New York and do not express
any opinion as to the laws of any other jurisdiction other than the laws of the
United States of America to the extent referred to specifically herein.

         Based on the foregoing I am of the opinion that:

         1. The Company has been duly incorporated and is validly existing as a
corporation in good standing under the laws of the State of New York.

         2. Each of the Indentures has been duly authorized by the Company and,
when executed and delivered by the Company, will be a valid and 



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binding agreement, enforceable against the Company in accordance with its terms,
except to the extent that enforcement thereof may be limited by (a) bankruptcy,
insolvency, reorganization, fraudulent transfer, moratorium or other similar
laws now or hereafter in effect relating to creditors' rights generally, (b)
general principles of equity (regardless of whether enforceability is considered
in a proceeding at law or in equity), (c) public policy considerations which may
limit the rights of parties to obtain further remedies, (d) requirements that a
claim with respect to any Debt Securities denominated other than in United
States dollars (or a judgment denominated other than in United States dollars in
respect of such claim) be converted into United States dollars at a rate of
exchange prevailing on a date determined pursuant to applicable law, and (e)
governmental authority to limit, delay or prohibit the making of payments
outside the United States or in foreign currencies, currency units or composite
currencies.

         3. With respect to any series of Debt Securities (the "Offered Debt
Securities"), when (i) an appropriate Prospectus Supplement with respect to the
Offered Debt Securities has been prepared, delivered and filed in compliance
with the Securities Act and the applicable rules and regulations thereunder;
(ii) if the Offered Debt Securities are to be sold pursuant to a firm commitment
underwritten offering, the Underwriting Agreement with respect to the Offered
Debt Securities has been duly authorized, executed and delivered by the Company
and the other parties thereto; (iii) the terms of the Offered Debt Securities
and of their issuance and sale have been duly established in conformity with the
applicable Indenture so as not to violate any applicable law, the Restated
Certificate of Incorporation or By-laws of the Company or result in a default
under or breach of any agreement or instrument binding upon the Company and so
as to comply with any requirement or restriction imposed by any court or
governmental body having jurisdiction over the Company; (iv) the applicable
Indenture has been qualified under the Trust Indenture Act of 1939, as amended,
and duly executed and delivered by the Company to the applicable Trustee; and
(v) the Offered Debt Securities have been duly executed and authenticated in
accordance with the provisions of the applicable Indenture and duly delivered to
the purchasers thereof upon payment of the agreed-upon consideration therefor,
(1) the Offered Debt Securities (including any Debt Securities duly issued upon
exercise of any Warrants), when issued and sold in accordance with the
applicable Indenture and 



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the applicable Underwriting Agreement or any other duly authorized, executed and
delivered applicable valid and binding purchase agreement will be valid and
binding obligations of the Company, enforceable against the Company in
accordance with their respective terms, except to the extent that enforcement
thereof may be limited by (a) bankruptcy, insolvency, reorganization, fraudulent
transfer, moratorium or other similar laws now or hereafter in effect relating
to creditors, rights generally, (b) general principles of equity (regardless of
whether enforceability is considered in a proceeding at law or in equity), (c)
public policy considerations which may limit the rights of parties to obtain
further remedies, (d) requirements that a claim with respect to any Offered Debt
Securities denominated other than in United States dollars (or a judgment
denominated other than in United States dollars in respect of such claim) be
converted into United States dollars at a rate of exchange prevailing on a date
determined pursuant to applicable law, and (e) governmental authority to limit,
delay or prohibit the making of payments outside the United States or in foreign
currencies, currency units or composite currencies; and (2) if Common Stock is
issuable upon conversion or exchange of any convertible Securities, the Common
Stock issuable upon conversion or exchange of such Securities will be validly
issued, fully paid and nonassessable, assuming the execution, authentication,
issuance and delivery of the Securities and conversion or exchange of the
Securities in accordance with the terms of the applicable indenture relating
thereto.

         4. With respect to the shares of any series of Preferred Stock,
including, if applicable, Depositary Shares representing fractional interests in
any Preferred Stock (together, the "Offered Preferred Stock"), when (i) an
appropriate Prospectus Supplement with respect to the shares of the Offered
Preferred Stock has been prepared, delivered and filed in compliance with the
Securities Act and the applicable rules and regulations thereunder; (ii) if the
Offered Preferred Stock is to be sold pursuant to a firm commitment underwritten
offering, the Underwriting Agreement with respect to the shares of the Offered
Preferred Stock has been duly authorized, executed and delivered by the Company
and the other parties thereto; (iii) the Board, including any appropriate
committee appointed thereby, and appropriate officers of the Company have taken
all necessary corporate action to approve the issuance and terms of the shares
of the offered Preferred Stock and related matters, including the adoption of a
Certificate of Designation



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for the Offered Preferred Stock in accordance with the applicable provisions of
New York law (the Certificate of Designation"); (iv) the filing of the
Certificate of Designation with the Secretary of State of the State of New York
has duly occurred; (v) the terms of the Offered Preferred Stock and of their
issuance and sale have been duly established in conformity with the Company's
Restated Certificate of Incorporation, including the Certificate of Designation
relating to the Offered Preferred Stock, and the By-laws of the Company so as
not to violate any applicable law, the Restated Certificate of Incorporation or
By-laws of the Company or result in a default under or breach of any agreement
or instrument binding upon the Company and so as to comply with any requirement
or restriction imposed by any court or governmental body having jurisdiction
over the Company; (vi) in the case of Depositary Shares, the Depositary
Agreement has been duly executed and delivered; and (vii) certificates
representing the shares of the Offered Preferred Stock are duly executed,
countersigned, registered and delivered upon payment of the agreed-upon
consideration therefor (and, in the case of Depositary Shares, such Preferred
Stock certificates are delivered to the Depositary for deposit in accordance
with the laws of the State of New York against issuance of the Receipts
evidencing the Depositary Shares in accordance with the terms of the Deposit
Agreement), (1) the shares of the offered Preferred Stock (including any
Preferred Stock duly issued upon exercise of any Warrants), when issued and sold
in accordance with the applicable Underwriting Agreement or any other duly
authorized, executed and delivered applicable valid and binding purchase
agreement, will be duly authorized, validly issued, fully paid and
nonassessable, provided that the consideration therefor is not less than the par
value thereof; and (2) if the Offered Preferred Stock is convertible or
exchangeable into Common Stock, the Common Stock issuable upon conversion or
exchange of the Offered Preferred Stock will be duly authorized, validly issued,
fully paid and nonassessable, assuming the execution, authentication, issuance
and delivery of the Offered Preferred Stock and the conversion or exchange of
the Offered Preferred Stock in accordance with the terms of the Certificate of
Designation.

         5. With respect to any offering of Common Stock, when (i) an
appropriate Prospectus Supplement with respect to the Common Stock has been
prepared, delivered and filed in compliance with the Securities Act and the
applicable



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rules and regulations thereunder; (ii) if the Common Stock is to be sold
pursuant to a firm commitment underwritten offering, the Underwriting Agreement
with respect to the Common Stock has been duly authorized, executed and
delivered by the Company and the other parties thereto; (iii) the terms of the
issuance and sale of the Common Stock have been duly established in conformity
with the Restated Certificate of Incorporation and By-laws so as not to violate
any applicable law, the Restated Certificate of Incorporation or By-laws of the
Company or result in a default under or breach of any agreement or instrument
binding upon the Company and so as to comply with any restriction imposed by any
court or governmental body having jurisdiction over the Company; and (iv)
certificates representing the shares of Common Stock are duly executed,
countersigned, registered and delivered upon payment of the agreed-upon
consideration therefor, the shares of Common Stock (including any duly issued
upon exercise of any Warrants), when issued and sold in accordance with the
Underwriting Agreement with respect to the Common Stock or any other duly
authorized, executed and delivered applicable valid and binding purchase
agreement, will be duly authorized, validly issued, fully paid and
nonassessable, provided that the consideration therefor is not less than the par
value thereof.

         6. With respect to the issuance of any series of Warrants (the "Offered
Warrants"), when (i) an appropriate Prospectus Supplement with respect to the
offered Warrants has been prepared, delivered and filed in compliance with the
Securities Act and the applicable rules and regulations thereunder; (ii) the
warrant agreement relating to the Offered Warrants (the "Warrant Agreement") in
the form to be filed as an exhibit to the Registration Statement, any amendment
thereto or any document incorporated by reference therein has been duly executed
and delivered as contemplated by the Board Resolutions; (iii) the terms of the
Offered Warrants and of their issuance and sale have been duly established in
conformity with the Warrant Agreement relating to such Offered Warrants so as
not to violate any applicable law, the Restated Certificate of Incorporation or
By-laws of the Company or result in a default under or breach of any agreement
or instrument binding upon the Company and so as to comply with any requirement
or restriction imposed by any court or governmental body having jurisdiction
over the Company; (iv) the Offered Warrants have been duly executed, delivered
and countersigned, in accordance with the Warrant Agreement relating to such

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Offered Warrants, and duly issued and sold in the applicable form to be filed as
an exhibit to the Registration Statement or any amendment thereto and in the
manner contemplated in the Registration Statement and any Prospectus Supplement
relating thereto; and (v) if the offered Warrants are to be sold pursuant to a
firm commitment underwritten offering, the Underwriting Agreement with respect
to the Offered Warrants has been duly authorized, executed and delivered by the
Company and the other parties thereto; such Offered Warrants will be valid and
binding obligations of the Company, enforceable against the Company in
accordance with their respective terms, except to the extent that enforcement
thereof may be limited by (a) bankruptcy, insolvency, reorganization, fraudulent
transfer, moratorium or other similar laws now or hereafter in effect relating
to creditors' rights generally, (b) general principles of equity (regardless of
whether enforceability is considered in a proceeding at law or in equity), and
(c) public policy considerations which may limit the rights of parties to obtain
further remedies.

         7. With respect to the Guarantee, when (i) the Registration Statement,
as finally amended (including all necessary post-effective amendments), has
become effective under the Securities Act; (ii) an appropriate Prospectus
Supplement with respect to the Guarantee has been prepared, delivered and filed
in compliance with the Securities Act and the applicable rules and regulations
thereunder; (iii) the Board, including any appropriate committee appointed
thereby, and appropriate officers of the Company have taken all necessary
corporate action to approve the terms of such Guarantee and related matters;
(iv) the Declaration has been duly executed and delivered by the parties thereto
and duly qualified under the Trust Indenture Act of 1939, as amended (the "Trust
Indenture Act"); (v) the Guarantee has been duly executed and delivered by the
parties thereto and duly qualified under the Trust Indenture Act; (vi) the terms
of the Trust Preferred Securities have been established in accordance with the
Declaration; (vii) the underwriting agreement with respect to such Trust
Preferred Securities has been duly authorized, executed and delivered by the
parties thereto; and (viii) the Trust Preferred Securities have been delivered
and paid for in the manner contemplated in the Registration Statement or any
Prospectus Supplement relating thereto and have been executed, authenticated and
issued in accordance with the Declaration, the Guarantee will be a valid and


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binding agreement of the Company, enforceable against the Company in accordance
with its terms, except to the extent that enforcement thereof may be limited by
(a) bankruptcy, insolvency, reorganization, fraudulent transfer, moratorium or
other similar laws now or hereafter in effect relating to creditors' rights
generally, (b) general principles of equity (regardless of whether
enforceability is considered in a proceeding at law or in equity), and (c)
public policy consideration which may limit the rights of parties to obtain
further remedies.
         I hereby consent to the filing of this opinion with the Commission as
Exhibit 5 to the Registration Statement. I also consent to the reference to me
under the heading "Validity of the Securities" in the Registration Statement. In
giving this consent, I do not thereby admit that I am in the category of persons
whose consent is required under Section 7 of the Securities Act or the rules and
regulations of the Commission promulgated thereunder.

                                              Very truly yours,
                                              /s/ James W. Guedry


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