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                                                             EXHIBIT 99.906 CERT

EXHIBIT 12(b)

SECTION 906 CERTIFICATIONS

                            SECTION 906 CERTIFICATION

        Michael E. Kenneally, Chief Executive Officer, and Michael A. Pignataro,
Chief Financial Officer, of Credit Suisse Opportunity Funds (the "Fund"), each
certify to his knowledge that:

(1)     The Fund's periodic report on Form N-CSR for the period ended October
     31, 2004 (the "Report") fully complies with the requirements of Section
     13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2)     The information contained in the Report fairly presents, in all material
respects, the financial condition and results of operations of the Fund.


     /s/ Michael E. Kenneally                        /s/ Michael A. Pignataro
     ------------------------                        ------------------------
     Michael E. Kenneally                            Michael A. Pignataro
     Chief Executive Officer                         Chief Financial Officer
     January 7, 2005                                 January 7, 2005

A signed original of this written statement required by Section 906, or other
document authenticating, acknowledging, or otherwise adopting the signature that
appears in typed form within the electronic version of this written statement
required by Section 906, has been provided to the Fund and will be retained by
the Fund and furnished to the Securities and Exchange Commission or its staff
upon request.

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