EXHIBIT 5

                   [Letterhead of Alcan's Corporate Secretary]

                                                                          , 2003

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549

            Re:  Registration Statement on Form S-4

Ladies and Gentlemen:

            I have acted as counsel for Alcan Inc., a Canadian corporation (the
"Company"), in connection with the registration under the Securities Act of
1933, as amended (the "Act"), of up to U.S. dollar - Common Shares (the "Common
Share"), without nominal or par value of the Company, as contemplated in the
Company's Registration Statement on Form S-4 being filed on the date hereof with
the Securities and Exchange Commission (the "Commission") under the Act (the
"Registration Statement"). I hereby consent to the use of this opinion in the
Registration Statement and to the references on pages - and - of the prospectus
forming a part of the Registration Statement and under the headings "Validity of
the Securities" and "Service of Process and Enforceability of Civil Liabilities
Under U.S. Securities Laws." In giving such consent I do not thereby admit that
I am in the category of persons whose consent is required under Section 7 of the
Act.

            In reaching the conclusions expressed in this opinion, I have
examined such certificates of public officials and of corporate officers and
directors and such other documents and matters as I have deemed necessary or
appropriate, relied upon the accuracy of facts and information set forth in all
such documents, and assumed the genuineness of all signatures, the authenticity
of all documents submitted to me as originals, the conformity to original
documents of all documents submitted to me as copies, and the authenticity of
the originals from which all such copies were made.

            Based on the foregoing, I am of the opinion that the Common Shares,
upon due execution by proper officers of the Company and delivery thereof
against payment of the purchase price thereof, will be legally issued, fully
paid and non-assessable.

            The foregoing opinion is limited to matters involving the laws of
Canada and the Province of Quebec.

                                    Very truly yours,