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                                                                      EXHIBIT 15

               LETTER RE: UNAUDITED INTERIM FINANCIAL INFORMATION

The Board of Directors
PacifiCare Health Systems, Inc.

We are aware of the incorporation by reference in the Registration Statement
(Form S-8 number 333-44038) and related Prospectus pertaining to the 2000
Employee Plan and 2000 Non-Employee Directors Plan of PacifiCare Health Systems,
Inc. and in the Registration Statement (Form S-8 number 333-49272) and related
Prospectus pertaining to the 1996 Stock Option Plan for Officers and Key
Employees and the related Prospectus pertaining to the 1996 Non-Officer
Directors Stock Option Plan of PacifiCare Health Systems, Inc. and in the
Registration Statement (Form S-8 number 333-48377) and related Prospectus
pertaining to the 1997 Premium Priced Stock Option Plan and the related
Prospectus pertaining to the Amendment and Restatement of the PacifiCare Health
Systems, Inc. Savings and Profit-Sharing Plan of PacifiCare Health Systems, Inc.
of our report dated October 31, 2000 relating to the unaudited condensed
consolidated interim financial statements of PacifiCare Health Systems, Inc.
that are included in its Form 10-Q for the quarters ended September 30, 2000 and
1999.

                                                          ERNST & YOUNG LLP

Irvine, California
November 6, 2000



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