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                                                                   EXHIBIT 10.06


                               FIRST AMENDMENT TO
                      SENIOR EXECUTIVE EMPLOYMENT AGREEMENT

This First Amendment to Senior Executive Employment Agreement, dated as of March
30, 2001 (the "Amendment"), hereby amends the Senior Executive Employment
Agreement, dated as of March 30, 2001 (the "Agreement"), between PacifiCare
Health Systems, Inc., a Delaware corporation (the "Company"), and John F Fritz,
an individual ("Executive"), as follows:

     1. AMENDMENT OF SECTION 2.1 OF THE AGREEMENT. The parties hereby amend the
Agreement by adding the following sentences at the end of Section 2.1:

     In the event that at the end of the term of this Agreement, the Company
     neither renews the Agreement nor offers Executive a new employment
     agreement, then Executive's employment with the Company shall terminate
     pursuant to section 2.2(d) of this Agreement. If the Company offers
     Executive a new employment agreement but Executive does not accept the new
     employment agreement, then Executive's continued employment with the
     Company will be without the benefit of a written employment agreement, in
     which case Executive's entitlement to severance benefits on termination
     shall be governed by then-existing Company policies and practices.

     2. LIMITATION OF AMENDMENTS. Except as expressly provided herein, no terms
or provisions of any agreement or instrument are modified or changed by this
Amendment and the terms and provisions of the Agreement, as amended by this
Amendment, shall continue in full force and effect.

     3. GOVERNING LAW. This Amendment shall be construed, interpreted and
enforced in accordance with, and governed by California law.

     4. CAPITALIZED TERMS. Capitalized terms not defined herein shall have the
meanings ascribed to them in the Agreement.

     5. DUPLICATE ORIGINALS; EXECUTION IN COUNTERPARTS. This Amendment may be
executed in two or more counterparts, each of which shall be an original but all
of which together shall constitute one and the same instrument.

     6. WAIVERS AND AMENDMENTS. Neither this Amendment nor any term hereof may
be changed, waived, discharged or terminated orally, or by any action or
inaction, but only by an instrument in writing signed by the party against which
enforcement of the change, waiver, discharge or termination is sought.

     7. SECTION HEADINGS. The titles of the sections hereof appear as a matter
of convenience only, do not constitute a part of this Amendment and shall not
affect the construction hereof.

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     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the date first written above.

The Company:                            PACIFICARE HEALTH SYSTEMS, INC.,
                                        a Delaware corporation


                                        ----------------------------------------
                                        By: Howard G. Phanstiel
                                        Title: President and
                                               Chief Executive Officer



Executive:                              ----------------------------------------
                                                   John F Fritz