Exhibit 5.1

Board of Directors of                                          December 31, 2003
The St. Joe Company
245 Riverside Avenue
Suite 500
Jacksonville, FL  32202

Re:   Registration Statement

Dear Sirs:

I am General Counsel of The St. Joe Company, a Florida corporation (the
"Company"). The Company is filing a Registration Statement on Form S-3 (the
"Registration Statement") with the Securities and Exchange Commission (the
"Commission") in connection with the registration under the Securities Act of
1933, as amended (the "Securities Act"), of 6,000,000 shares (the "Shares") of
the Company's Common Stock, no par value (the "Common Stock"), to be sold by the
selling shareholder named in the Registration Statement. The selling shareholder
proposes to sell the Shares pursuant to the Plan of Distribution set forth in
the Registration Statement.

I have examined the originals, or photostatic or certified copies, of such
records of the Company and certificates of officers of the Company and of public
officials and such other documents as I have deemed relevant and necessary as
the basis for the opinion set forth below. In such examination, I have assumed
the genuineness of all signatures, the authenticity of all documents submitted
to me as certified or photostatic copies and the authenticity of the originals
of such copies.

Based on the foregoing and in reliance thereon, and subject to the assumptions,
exceptions, qualifications and limitations set forth herein, I am of the opinion
that the Shares have been validly issued and are fully paid and non-assessable.

I render no opinion herein as to matters involving the laws of any jurisdiction
other than the laws of the United States of America and the Business Corporation
Act of the State of Florida. In rendering this opinion, I assume no obligation
to revise or supplement this opinion should current laws, or the interpretations
thereof, be changed.

I consent to the filing of this opinion as an exhibit to the Registration
Statement, and I further consent to the use of my name under the caption "Legal
Matters" in the Registration Statement and the prospectus which forms a part
thereof. In giving these consents, I do not thereby admit that I am within the
category of persons whose consent is required under Section 7 of the Securities
Act or the Rules and Regulations of the Commission.

Very truly yours,


/s/ Christine M. Marx