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                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

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                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER

                    PURSUANT TO RULE 13a-16 OR 15d-16 OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                            For the month of May 2006

                        Commission File Number: 000-16977

                               STOLT-NIELSEN S.A.
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                 (Translation of registrant's name into English)

                            c/o Stolt-Nielsen Limited
                                  Aldwych House
                                  71-91 Aldwych
                                 London WC2B 4HN
                                     ENGLAND
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                    (Address of principal executive offices)

     Indicate by check mark whether the registrant files or will file annual
reports under cover Form 20-F or Form 40-F.

                    Form 20-F [X]              Form 40-F [ ]

     Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101(b)(1): [ ]

     Indicate by check mark if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101(b)(7): [ ]

     Indicate by check mark whether by furnishing the information contained in
this Form, the registrant is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

                    Yes [ ]                    No [X]

     If "Yes" is marked, indicate below the file number assigned to the
registrant in connection with Rule 12g3-2(b): 82-________

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In accordance with General Instruction B, item (iii), attached herewith as
Exhibit 99.1 is a press release, dated May 15, 2006, announcing that
Stolt-Nielsen Transportation Group, a 100% owned subsidiary of Stolt-Nielsen
S.A. ("SNSA"), purchased 589,450 of SNSA's Common Shares on the Oslo Stock
Exchange in accordance with SNSA's share repurchase program. The share
repurchase program was announced on August 25, 2005 and authorizes the purchase
of up to $200 million worth of SNSA's Common Shares or related American
Depositary Shares.

The attached press release shall be deemed to be incorporated by reference into
the prospectuses forming a part of SNSA's Registration Statements on Form S-8
(No. 33-28473, No. 333-6900, No. 333-11178 and No. 333-121315) and to be a part
of such prospectuses from the date of the filing thereof.

The attached press release contains "forward-looking statements" within the
meaning of Section 27A of the Securities Act of 1933 and Section 21E of the
Securities Exchange Act of 1934. These statements may be identified by the use
of words like "anticipate," "believe," "estimate," "expect," "intend," "may,"
"plan," "project," "will," "should," "seek," and similar expressions. The
forward-looking statements reflect SNSA's current views and assumptions and are
subject to risks and uncertainties. The following factors, and others which are
discussed in SNSA's public filings and submissions with the U.S. Securities and
Exchange Commission, are among those that may cause actual and future results
and trends to differ materially from SNSA's forward-looking statements: the
general economic conditions and competition in the markets and businesses in
which SNSA operates; changes in the supply of and demand for parcel tanker, tank
container and terminal capacity in the markets in which SNSA operates; changes
in the supply of and demand for the products SNSA transport, particularly the
bulk liquids, chemicals and other specialty liquids that form the majority of
the products that SNSA transports; prevailing market rates for the
transportation services that SNSA offers and the fish products that SNSA sells;
changes in bunker fuel prices; the cost and feasibility of maintaining and
replacing SNSA's older ships and building or purchasing new ships; uncertainties
inherent in operating internationally; the outcome of legal proceedings; SNSA's
relationship with significant customers; the outcome of discussions with
customers concerning potential antitrust claims; the impact of negative
publicity; environmental challenges and natural conditions facing SNSA's
aquaculture business; the impact of laws and regulations; operating hazards,
including marine disasters, spills or environmental damage; the conditions and
factors that may influence the decision to issue future dividends; and the
market for long-term debt. Many of these factors are beyond SNSA's ability to
control or predict. Given these factors, you should not place undue reliance on
the forward-looking statements. Should one or more of these risks or
uncertainties occur, or should management's assumptions or estimates prove
incorrect, actual results and events may vary materially from those discussed in
the forward-looking statements.

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                                    SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.

                                                     STOLT-NIELSEN S.A.


Date: May 16, 2006                                   By: /s/ Alan B. Winsor
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                                                     Name:  Alan B. Winsor
                                                     Title: Attorney-in-Fact

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