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                                                                   EXHIBIT 10.32

                         PACIFICARE HEALTH SYSTEMS, INC.
                             3120 Lake Center Drive
                            Santa Ana, CA 92704-6917




March 7, 2001

UniHealth Foundation
3400 Riverside Drive
Burbank, California 91505
Attention:  David R. Carpenter

RE:  MODIFICATION OF STOCK PURCHASE AGREEMENT

Ladies and Gentlemen:

This letter (the "Letter Agreement") is written to confirm our agreement
regarding the modification of the Stock Purchase Agreement, dated May 4, 1999,
by and between PacifiCare Health Systems, Inc. ("PacifiCare") and UniHealth
Foundation ("UniHealth"), as modified by that certain letter agreement, dated
February 8, 2001 (the "Stock Purchase Agreement"). Capitalized terms used but
not defined herein shall have the meanings given to them in the Stock Purchase
Agreement.

Under the Stock Purchase Agreement, PacifiCare agreed to purchase, and UniHealth
agreed to sell the shares of PacifiCare Common Stock held by UniHealth, subject
to and in accordance with the terms of the Stock Purchase Agreement. The parties
disagree as to whether the Stock Purchase Agreement including the right of first
refusal contained therein, continues in effect. If the Stock Purchase Agreement
and the right of first refusal are in effect, the right of first refusal is
waived as to those Remaining Shares (as defined below) that UniHealth sells in
accordance with this Letter Agreement.



1.      PacifiCare agrees that, notwithstanding subsections 7.1(d), 7.1(k) and
        9.2 of the Stock Purchase Agreement, UniHealth may sell its remaining
        shares of PacifiCare stock of approximately three million six hundred
        ninety-four thousand five hundred (3,694,500) shares (the "Remaining
        Shares") in one or more open market sales in accordance with the shelf
        registration statement on file with the Securities and Exchange
        Commission in accordance with the Registration Rights Agreement, dated
        May 4, 1999, between PacifiCare and UniHealth or sales made pursuant to
        Rule 144 promulgated under the Securities Act of 1933, as amended and
        only on days that the trading window is open under the PacifiCare
        Insider Trading Policy; provided, however, that:


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UniHealth Foundation
March 7, 2001
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               (i)    the number of Remaining Shares sold during the term of
                      this Letter Agreement does not exceed the volume
                      limitations contained in Rule 144 promulgated under the
                      Securities Act of 1933, as amended, for affiliates; and

               (ii)   on any given day UniHealth does not sell more than the
                      greater of: (a) two hundred fifty thousand (250,000) of
                      the Remaining Shares or (b) twenty-five percent (25%) of
                      the trading volume of PacifiCare's common stock for the
                      immediately preceding trading day.

2.      This Letter Agreement shall terminate on June 15, 2001. It is
        PacifiCare's position that any sale of the Remaining Shares after June
        15, 2001 shall be conducted as contemplated by the Stock Purchase
        Agreement prior to this modification. It is UniHealth's position that
        any sales of the Remaining Shares after June 15, 2001 will not be
        subject to the restrictions of subsections 7.1 and 9.2 of the Stock
        Purchase Agreement.


3.      Except as expressly stated herein, the parties do not intend to modify
        the Stock Purchase Agreement.

4.      The Stock Purchase Agreement and any other agreement entered into
        contemporaneously therewith, together with this Letter Agreement, set
        forth the entire agreement of the parties and are intended to supersede
        all prior negotiations, understandings, and agreements and cannot be
        altered, amended, changed or modified in any respect or particular
        unless each such alteration, amendment, change or modification shall
        have been agreed to by PacifiCare and UniHealth and reduced to writing
        in its entirety and signed and delivered by each party.

5.      This Letter Agreement may be executed in counterparts, each of which
        together shall comprise one and the same instrument.


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UniHealth Foundation
March 7, 2001
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Please confirm your acceptance to the terms and provisions of this agreement by
signing below.


Very truly yours,

PACIFICARE HEALTH SYSTEMS, INC.


By:
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Its:
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AGREED AND ACCEPTED:

UNIHEALTH FOUNDATION


By:
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Its:
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