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                                                                   Exhibit 10.20

                                 June 16, 1999




Dear Bill:

                  This letter (the "Agreement") is to confirm the agreement
between you and Hyperion Solutions Corporation (the "Company") regarding your
separation from the Company.

                  1.    You understand and agree that your employment with the
                        Company terminated on June 2, 1999 (the "Termination
                        Date"). Provided that you do not revoke this Agreement
                        within the revocation period set forth in paragraph 14
                        below, the Company shall:

                        (a)  within three (3) business days following the
                             effective date of this Agreement, pay you a lump
                             sum severance payment of Two Hundred Thirty-Five
                             Thousand One Hundred Sixty-Six and 67/100 Dollars
                             ($235,166.67), less all applicable withholdings;
                             such payment shall be wire transferred to the
                             account into which the Company has previously
                             deposited your salary and other compensation
                             payments;

                        (b)  pay your COBRA payments through and until June 2,
                             2000 if you elect to continue medical insurance
                             coverage for you, your wife and son pursuant to
                             COBRA; and

                        (c)  cause all 80,000 unexercised options granted to you
                             prior to August 24, 1998 to become exercisable
                             immediately for fully vested shares.

                        You agree that the remaining 50,000 options granted to
                        you on September 9, 1998 and the 16,000 options granted
                        to you on February 24, 1999 terminated on June 2, 1999,
                        and will never become exercisable. You further agree
                        that the options described in subparagraph (c) above
                        will terminate on September 2, 1999.

                        The Company will use its best efforts to, within five
                        (5) business days of the effective date of this
                        Agreement, present to the Board for its adoption Board
                        resolutions regarding the Company's obligations set
                        forth in subparagraph (c) above.

                  2.    You agree that you have been paid all of your accrued
                        but unused vacation and all of your salary and
                        commissions earned through your Termination Date, and
                        except as expressly set forth herein, or in the
                        Indemnification Agreement entered into between you and
                        the Company concurrent with the execution of this
                        Agreement (the "Indemnification Agreement"), a


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                        copy of which is attached hereto as Exhibit A, you are
                        not entitled to any further money or benefits from the
                        Company.

                  3.    In consideration for the mutual promises and
                        consideration described in this letter, you and the
                        Company hereby waive and release and promise never to
                        assert any claims or causes of action, whether or not
                        now known, against the other party or his or its past or
                        present predecessors, successors, subsidiaries,
                        officers, directors, agents, employees, employee benefit
                        plans and assigns, with respect to any matter, including
                        but not limited to, any matter arising out of or
                        connected with your employment with the Company or the
                        termination of that employment, including without
                        limitation, claims of wrongful discharge, emotional
                        distress, defamation, fraud, breach of contract, breach
                        of the covenant of good faith and fair dealing, any
                        claims of discrimination or harassment based on sex,
                        age, race, national origin, disability or on any other
                        basis, under Title VII of the Civil Rights Act of 1964,
                        as amended, the California Fair Employment and Housing
                        Act, the Age Discrimination in Employment Act of 1967,
                        as amended, and all other laws and regulations relating
                        to employment.

                  4.    You and the Company expressly waive and release any and
                        all rights and benefits under Section 1542 of the Civil
                        Code of the State of California (or any analogous law of
                        any other state), which reads as follows: "A general
                        release does not extend to claims which the creditor
                        does not know or suspect to exist in his favor at the
                        time of executing the release, which, if known by him,
                        must have materially affected his settlement with the
                        debtor."

                  5.    Nothing contained in this letter shall constitute or be
                        treated as an admission by you or the Company of
                        liability, of any wrongdoing, or of any violation of
                        law.

                  6.    At all times in the future, you will remain bound by the
                        Company's Proprietary Information and Invention
                        Agreement signed by you, a copy of which is attached as
                        Exhibit B.

                  7.    At all times in the future, you agree not to make any
                        derogatory statements regarding the Company or any of
                        the members of the Board to any third party. The Company
                        and Board also agree that neither the Board nor any
                        individual member of the Board or present section 16
                        officer of the Company shall make any derogatory
                        statements regarding you to any party outside the
                        Company; provided, however, that nothing in this
                        Agreement shall prohibit the parties from responding to
                        any inquiry regarding your separation from the Company
                        by stating that you and the Board had different views
                        regarding the management of the Company.



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                  8.    You agree that during the two (2) year period commencing
                        on the effective date of this Agreement, you shall not
                        directly or indirectly, personally or on behalf of any
                        other party:

                        (a)  engage in a Competitive Business Activity in any of
                             the locations listed in Exhibit C attached hereto.
                             The term "Competitive Business Activity" shall
                             mean:

                             (i)   engaging in, or managing or directing persons
                                   engaged in, any business in which the Company
                                   or any of the Company's affiliates was
                                   engaged as of the Termination Date, whether
                                   independently or as an employee, agent,
                                   consultant, advisor, independent contractor,
                                   proprietor, partner, officer, director or
                                   otherwise;

                             (ii)  acquiring or having an ownership interest in
                                   any entity that derives more than 15% of its
                                   gross revenues from any business in which the
                                   Company or any of the Company's affiliates
                                   was engaged as of the Termination Date,
                                   except for ownership of 1% or less of any
                                   entity whose securities are freely tradable
                                   on an established market;

                             (iii) participating in the financing, operation,
                                   management or control of any firm,
                                   partnership, corporation, entity or business
                                   described in Paragraph (ii) above; or

                        (b)  solicit or attempt to solicit either:

                             (i)   any employee of the Company or any of the
                                   Company's affiliates to terminate the
                                   employee's employment with the Company; or

                             (ii)  the business of any customer of the Company
                                   or its affiliates with whom you had contact
                                   during your employment with the Company.

                  9.    At all times in the future the Company and you will
                        remain bound by the Indemnification Agreement,
                        including, without limitation, the Company's obligation
                        to indemnify you against all expenses and costs as
                        expressly set forth in the Indemnification Agreement.

                  10.   You agree that you will not disclose to others the fact
                        or terms of this letter, except that you may disclose
                        such information to: (a) your attorney or accountant in
                        order for such individuals to render services to you; or
                        (b) your spouse. You further agree that you will
                        instruct such individuals that they may not disclose any
                        such information to any other party at any time in the
                        future.



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                  11.   You represent and warrant that, except for the IBM
                        Thinkpad computer, which the Company hereby agrees may
                        be retained by you, you have returned to the Company all
                        of its property, including, but not limited to, any and
                        all Company files, documents (including any written or
                        electronic versions thereof) and physical property.

                  12.   You agree that except as expressly provided in this
                        letter, this letter renders null and void any and all
                        prior agreements between you and the Company. You and
                        the Company agree that this Agreement, together with
                        Exhibits A, B and C, constitutes the entire agreement
                        between you and the Company regarding the subject matter
                        of this Agreement, and that this Agreement may be
                        modified only in a written document signed by you and a
                        duly authorized officer of the Company.

                  13.   This Agreement shall be construed and interpreted in
                        accordance with the laws of the State of California.

                  14.   You have up to twenty-one (21) days after receipt of
                        this letter within which to review it, and to discuss it
                        with an attorney of your own choosing regarding whether
                        or not you wish to execute it. Furthermore, you have
                        seven (7) days after you have signed this letter during
                        which time you may revoke this Agreement.

                  15.   If you wish to revoke this Agreement, you may do so by
                        delivering a letter of revocation to me. Because of this
                        revocation period, you understand that the agreement set
                        forth in this letter shall not become effective or
                        enforceable until the eighth day after the date you sign
                        this letter.

                  16.   This Agreement may be executed in counterparts, each of
                        which shall be an original, but all of which together
                        shall constitute one agreement.

                  Please indicate your agreement with the above terms by signing
below.

                                   Sincerely,


                                   /s/ Larry Braverman
                                   ____________________________________________
                                   Larry Braverman

                  My agreement with the above terms is signified by my signature
below. Furthermore, I acknowledge that I have read and understand this letter
and that I sign this release of all claims voluntarily, with full appreciation
that at no time in the future may I pursue any of the rights I have waived in
this release.

        6/16/99                    /s/ William Binch
Dated:_________________________    ____________________________________________
                                   William Binch



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