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                                                                    EXHIBIT 10.1


                              EMPLOYMENT AGREEMENT


                  THIS AGREEMENT is entered into on February 23, 1999, by and
between Stephen V. Imbler (the "Employee") and HYPERION SOLUTIONS CORPORATION, a
Delaware corporation (the "Company").

         1. DUTIES AND SCOPE OF EMPLOYMENT.

                  (a) POSITION. For the term of his employment under this
Agreement ("Employment"), the Company agrees to employ the Employee in the
position of Senior Vice President and Chief Financial Officer or in such other
position as the Company subsequently may assign to the Employee. The Employee
shall report to the Company's President and Chief Executive Officer or to such
other person as the Company subsequently may determine.

                  (b) OBLIGATIONS TO THE COMPANY. During the term of his
Employment, the Employee shall devote his full business efforts and time to the
Company. During the term of his Employment, without the prior written approval
of the Company (which shall not be unreasonably withheld), the Employee shall
not render services in any capacity to any other person or entity and shall not
act as a sole proprietor, partner or managing member of any other person or
entity or as a shareholder owning more than one percent of the stock of any
other corporation. The foregoing, however, shall not preclude the Employee from
engaging in reasonable community, school or charitable activities. The Employee
shall comply with the Company's policies and rules, as they may be in effect
from time to time during the term of his Employment.

                  (c) NO CONFLICTING OBLIGATIONS. The Employee represents and
warrants to the Company that he is under no obligations or commitments, whether
contractual or otherwise, that are inconsistent with his obligations under this
Agreement. The Employee represents and warrants that he will not use or
disclose, in connection with his employment by the Company, any trade secrets or
other proprietary information or intellectual property in which he or any other
person has any right, title or interest and that his employment by the Company
as contemplated by this Agreement will not infringe or violate the rights of any
other person. The Employee represents and warrants to the Company that he has
returned all property and confidential information belonging to any prior
employer.
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         2. CASH AND INCENTIVE COMPENSATION.

                  (a) SALARY. The Company shall pay the Employee as compensation
for his services a base salary at a gross annual rate of not less than $250,000
(two hundred fifty thousand dollars). Such salary shall be payable in accordance
with the Company's standard payroll procedures. (The annual compensation
specified in this Subsection (a), together with any increases in such
compensation that the Company may grant from time to time, is referred to in
this Agreement as "Base Compensation.").

                  (b) INCENTIVE BONUSES. The Employee shall be eligible to be
considered for an annual incentive bonus with a target amount of $150,000 (one
hundred fifty thousand dollars). Such bonus (if any) shall be awarded based on
objective or subjective criteria established in advance by the Company's Board
of Directors (the "Board") or its Compensation Committee. The determinations of
the Board or such Committee with respect to such bonus shall be final and
binding.

         3. VACATION AND EMPLOYEE BENEFITS. During the term of his Employment,
the Employee shall be eligible for paid vacations in accordance with the
Company's standard policy applicable to all of its employees, as it may be
amended from time to time. During the term of his Employment, the Employee shall
be eligible to participate in any employee benefit plans maintained by the
Company for similarly situated employees, subject in each case to the generally
applicable terms and conditions of the plan in question and to the
determinations of any person or committee administering such plan.

         4. BUSINESS EXPENSES. During the term of his Employment, the Employee
shall be authorized to incur necessary and reasonable travel, entertainment and
other business expenses in connection with his duties hereunder. The Company
shall reimburse the Employee for such expenses upon presentation of an itemized
account and appropriate supporting documentation, all in accordance with the
Company's generally applicable policies. Any single expenditure in excess of
$5,000 shall require the prior approval of the Company's Chief Executive Officer
or Chief Financial Officer.

         5. TERM OF EMPLOYMENT.

                  (a) BASIC RULE. The Company agrees to continue the Employee's
Employment, and the Employee agrees to remain in Employment with the Company,
from the Effective Time until the earlier of:

                           (i) The close of the applicable Initial Term or
                  Renewal Period, as determined under Subsection (b) below; or

                           (ii) The date when the Employee's Employment
                  terminates pursuant to Subsection (c) below.

                  (b) INITIAL TERM AND RENEWAL PERIODS. The initial term of this
Agreement shall end on January 31, 2001 (the "Initial Term"). Thereafter this
Agreement shall 



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automatically be renewed for successive 12-month periods (the "Renewal
Periods"), unless either party has given the other party written notice of
non-renewal not less than 90 days prior to the close of the Initial Term or
Renewal Period then in effect.

                  (c) EARLY TERMINATION. The Employee may terminate his
Employment at any time and for any reason (or no reason) by giving the Company
30 days' advance notice in writing. The Company may terminate the Employee's
Employment at any time and for any reason (or no reason), and with or without
Cause, by giving the Employee 30 days' advance notice in writing. The Company
may also terminate the Employee's active Employment due to Permanent Disability
by giving the Employee notice in writing. For all purposes under this Agreement,
"Permanent Disability" shall mean that the Employee, at the time notice is
given, has failed to perform his duties under this Agreement for 60 or more
consecutive days or for 90 or more days during any 12-month period as the result
of his incapacity due to physical or mental injury, disability or illness. The
Employee's Employment shall terminate automatically in the event of his death.

                  (d) EMPLOYMENT AT WILL. The Employee's Employment with the
Company shall be "at will." Any contrary representations which may have been
made to the Employee shall be superseded by this Agreement. This Agreement shall
constitute the full and complete agreement between the Employee and the Company
on the "at will" nature of the Employee's Employment, which may only be changed
in an express written agreement signed by the Employee and a duly authorized
officer of the Company.

                  (e) RIGHTS AND OBLIGATIONS UPON TERMINATION. Except as
expressly provided in Section 6, upon the termination of the Employee's
Employment pursuant to this Section 5, the Employee shall only be entitled to
the compensation, benefits and reimbursements described in Sections 2, 3 and 4
for the period preceding the effective date of the termination. No incentive
bonus under Section 2(b) shall be payable for the year in which the Employee's
Employment terminates, unless the applicable bonus program expressly provides
for the payment of a prorated bonus for such year. The payments under this
Agreement shall fully discharge all responsibilities of the Company to the
Employee. The termination of this Agreement shall not limit or otherwise affect
the Employee's obligations under Section 7.

         6. TERMINATION BENEFITS.

                  (a) GENERAL RELEASE. Any other provision of this Agreement
notwithstanding, Subsections (b) and (c) below shall not apply unless the
Employee (i) has executed a general release (in a form prescribed by the
Company) of all known and unknown claims that he may then have against the
Company or persons affiliated with the Company and (ii) has agreed not to
prosecute any legal action or other proceeding based upon any of such claims.

                  (b) SEVERANCE PAY. The Company shall pay the Employee his Base
Compensation for a 12-month period following the effective date of the
termination of his Employment (the "Continuation Period") if:

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                           (i) The Company terminates the Employee's Employment
                  under Section 5(c) for any reason other than Cause or
                  Permanent Disability; or

                           (ii) The Company was subject to a Change in Control
                  and, within 12 months thereafter, the Employee resigns for
                  Good Reason.

Base Compensation under this Subsection (b) shall be paid at the rate in effect
at the time of the termination of Employment and in accordance with the
Company's standard payroll procedures.

                  (c) EMPLOYEE BENEFITS. If Subsection (b) above applies, the
         Company shall continue the coverage of the Employee and his dependents
         (if applicable) under the employee benefit plans described in Section 3
         during the Continuation Period. To the extent that such plans or the
         insurance contracts or provider agreements associated with such plans
         do not permit the extension of the Employee's coverage following the
         termination of his active employment, the Company shall pay the
         Employee cash in an amount equal to the cost to the Company of the
         coverage that cannot be provided. The cash payments shall be made in
         accordance with Subsection (b) above.

                  (d) COBRA. If Subsection (b) above applies, and if the
         Employee elects to continue his health insurance coverage under the
         Consolidated Omnibus Budget Reconciliation Act ("COBRA") following the
         termination of his Employment, then the date of the "qualifying event"
         for purposes of COBRA shall be the Employee's last day of active
         employment.

                  (e) DEFINITION OF "CAUSE." For all purposes under this
         Agreement, "Cause" shall mean:

                           (i) The Employee's failure to perform in a
                  satisfactory fashion one or more reasonable and lawful duties
                  assigned to the Employee by the Company under this Agreement,
                  if such failure continues for 15 days or more after the
                  Company has given the Employee written notice describing such
                  failure and advising him of the consequences of such failure
                  under this Agreement; provided that such notice shall be
                  required only with respect to the first such failure;

                           (ii) The Employee's misconduct relating to the
                  Company's affairs, if such misconduct continues for 15 days or
                  more after the Company has given the Employee written notice
                  describing such misconduct and advising him of the
                  consequences of such misconduct under this Agreement; provided
                  that such notice shall be required only with respect to the
                  first occurrence of such misconduct;

                           (iii) The Employee's conviction of, or a plea of
                  "guilty" or "no contest" to, a felony under the laws of the
                  United States or any state thereof;

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                           (iv) The Employee's failure or refusal to carry out
                  the reasonable directives of the Company, if such failure
                  continues for three days or more after the Company has given
                  the Employee written notice describing such failure and
                  advising him of the consequences of such failure under this
                  Agreement; provided that such notice shall be required only
                  with respect to the first such failure;

                           (v) Any breach of this Agreement, the Proprietary
                  Information and Inventions Agreement between the Employee and
                  the Company, or any other agreement between the Employee and
                  the Company;

                           (vi) Threats or acts of violence directed at any
                  present, former or prospective employee, independent
                  contractor, vendor, customer or business partner of the
                  Company; or

                           (vii) Fraud or embezzlement involving the assets of
                  the Company or its affiliates, customers or suppliers.

The foregoing shall not be deemed an exclusive list of all acts or omissions
that the Company may consider as grounds for the termination of the Employee's
Employment without Cause.

                  (f) DEFINITION OF "CHANGE IN CONTROL." For all purposes under
this Agreement, "Change in Control" shall mean:

                           (i) The consummation of a merger or consolidation of
                  the Company with or into another entity or any other corporate
                  reorganization, if persons who were not stockholders of the
                  Company immediately prior to such transaction own immediately
                  after such transaction 50% or more of the voting power of the
                  outstanding securities of each of (A) the continuing or
                  surviving entity and (B) any direct or indirect parent
                  corporation of such continuing or surviving entity;

                           (ii) The sale, transfer or other disposition of all
                  or substantially all of the Company's assets, if persons who
                  were not stockholders of the Company immediately prior to such
                  transaction own immediately after such transaction 50% or more
                  of the voting power of the outstanding securities of each of
                  (A) the continuing or surviving entity and (B) any direct or
                  indirect parent corporation of such continuing or surviving
                  entity;

                           (iii) A change in the composition of the Board, as a
                  result of which fewer than a majority of the incumbent
                  directors are directors who either (A) had been directors of
                  the Company on the date 24 months prior to the date of the
                  event that may constitute a Change in Control (the "original
                  directors") or (B) were elected, or nominated for election, to
                  the Board with the affirmative votes of at least a majority of
                  the aggregate of the original directors who were still 



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                  in office at the time of the election or nomination and the
                  directors whose election or nomination was previously so
                  approved;
                           (iv) Any transaction as a result of which any person
                  is the "beneficial owner" (as defined in Rule 13d-3 under the
                  Securities Exchange Act of 1934, as amended (the "Exchange
                  Act")), directly or indirectly, of securities of the Company
                  representing more than 50% of the total voting power
                  represented by the Company's then outstanding voting
                  securities. For purposes of this Paragraph (iv), the term
                  "person" shall have the same meaning as when used in sections
                  13(d) and 14(d) of the Exchange Act but shall exclude (A) a
                  trustee or other fiduciary holding securities under an
                  employee benefit plan of the Company or of a parent or
                  subsidiary of the Company and (B) a corporation owned directly
                  or indirectly by the stockholders of the Company in
                  substantially the same proportions as their ownership of the
                  common stock of the Company; or

                           (v) Any change in control required to be reported by
                  Item 1 of Form 8-K of the Securities and Exchange Commission
                  or by Item 6(e) of Schedule 14A set forth in Rule 14a-101
                  under the Exchange Act (or by any successor of either).

A transaction shall not constitute a Change in Control if its sole purpose is to
change the state of the Company's incorporation or to create a holding company
that will be owned in substantially the same proportions by the persons who held
the Company's securities immediately before such transaction.

                  (g) DEFINITION OF "GOOD REASON." For all purposes under this
Agreement, "Good Reason" shall mean:

                           (i) A significant diminution in the nature or scope
                  of the Employee's authority, duties or responsibilities in
                  effect immediately prior to the Change in Control;

                           (ii) Any reduction in the rate of the Employee's Base
                  Compensation in effect immediately prior to the Change in
                  Control or a reduction of 25% or more in the value of the
                  Employee's aggregate compensation and benefits in effect
                  immediately prior to the Change in Control;

                           (iii) The relocation of the Employee's principal
                  place of employment to a site more than 25 miles removed from
                  his principal place of employment immediately prior to the
                  Change in Control; or

                           (iv) An increase of 25% or more in the average amount
                  of time per month that the Employee is required to be away
                  from his principal place of employment, relative to the
                  average amount of time per month that the Employee was
                  required to be away from his principal place of employment
                  immediately prior to the Change in Control.

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         7. EMPLOYEE'S COVENANTS.

                  (a) NON-SOLICITATION. During the period commencing on the date
of this Agreement and continuing until the second anniversary of the date when
the Employee's Employment terminated for any reason, the Employee shall not
directly or indirectly, personally or through others, solicit or attempt to
solicit (on the Employee's own behalf or on behalf of any other person or
entity) either (i) the employment of any employee of the Company or any of the
Company's affiliates or (ii) the business of any customer of the Company, or of
any of the Company's affiliates, with whom the Employee had contact during his
Employment. During such period, the Employee shall not encourage or induce, or
take any action that has the effect of encouraging or inducing, any employee of
the Company or any of the Company's affiliates to terminate his or her
employment.

                  (b) NON-DISCLOSURE. The Employee has entered into a
Proprietary Information and Inventions Agreement with the Company, which is
incorporated herein by reference.

                  (c) NON-COMPETITION. If Section 6(b) applies, the Employee
during the Continuation Period shall not, directly or indirectly (other than on
behalf of the Company or with the Company's prior written consent), engage in a
Competitive Business Activity in any of the locations listed in Schedule A
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 is engaged at the time of the termination
                  of the Employee's Employment, 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 is engaged at the time of the termination of the
                  Employee's Employment, except for ownership of 1% or less of
                  any entity whose securities are freely tradable on an
                  established market; or

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

                  (d) NON-DISPARAGEMENT. During the period commencing on the
date of this Agreement and continuing until the second anniversary of the date
when the Employee's Employment terminated for any reason, the Employee shall not
directly or indirectly, personally or through others, disparage the Company or
its management.

                  (e) INJUNCTIVE RELIEF. The Employee acknowledges and agrees
that his failure to perform any of his covenants in this Section 7 would cause
irreparable injury to the 


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Company and cause damages to the Company that would be difficult or impossible
to ascertain or quantify. Accordingly, without limiting any other remedies that
may be available with respect to any breach of this Agreement, the Employee
consents to the entry of an injunction to restrain any breach of this Section 7.

                  (f) SURVIVAL. The covenants in this Section 7 shall survive
any termination or expiration of this Agreement and the termination of the
Employee's Employment with the Company for any reason.

         8. SUCCESSORS.

                  (a) COMPANY'S SUCCESSORS. This Agreement shall be binding upon
any successor (whether direct or indirect and whether by purchase, lease,
merger, consolidation, liquidation or otherwise) to all or substantially all of
the Company's business and/or assets. For all purposes under this Agreement, the
term "Company" shall include any successor to the Company's business and/or
assets which becomes bound by this Agreement.

                  (b) EMPLOYEE'S SUCCESSORS. This Agreement and all rights of
the Employee hereunder shall inure to the benefit of, and be enforceable by, the
Employee's personal or legal representatives, executors, administrators,
successors, heirs, distributees, devisees and legatees.

         9. MISCELLANEOUS PROVISIONS.

                  (a) NOTICE. Notices and all other communications contemplated
by this Agreement shall be in writing and shall be deemed to have been duly
given when (i) personally delivered, (ii) delivered to the U.S. Postal Service
for delivery by registered or certified mail or (iii) delivered to a comparable
private service offering guaranteed deliveries in the ordinary course of its
business. Notice under clauses (ii) and (iii) shall be valid only if delivery
charges have been prepaid and a return receipt will be furnished. In the case of
the Employee, notice under clauses (ii) and (iii) shall be addressed to him at
the home address which he most recently communicated to the Company in writing.
In the case of the Company, notice under clauses (ii) and (iii) shall be
addressed to its corporate headquarters and directed to the attention of its
Secretary.

                  (b) MODIFICATIONS AND WAIVERS. No provision of this Agreement
shall be modified, waived or discharged unless the modification, waiver or
discharge is agreed to in writing and signed by the Employee and by an
authorized officer of the Company (other than the Employee). No waiver by either
party of any breach of, or of compliance with, any condition or provision of
this Agreement by the other party shall be considered a waiver of any other
condition or provision or of the same condition or provision at another time.

                  (c) WHOLE AGREEMENT. This Agreement supersedes any prior
employment agreement between the Employee and the Company. No other agreements,
representations or understandings (whether oral or written and whether express
or implied) which are not expressly set forth in this Agreement have been made
or entered into by either party with 


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respect to the subject matter hereof. This Agreement and the Proprietary
Information and Inventions Agreement between the Employee and the Company
contain the entire understanding of the parties with respect to the subject
matter hereof.

                  (d) WITHHOLDING TAXES. All payments made under this Agreement
shall be subject to reduction to reflect taxes or other charges required to be
withheld by law.

                  (e) CHOICE OF LAW. The validity, interpretation, construction
and performance of this Agreement shall be governed by the laws of the State of
California (except their provisions governing the choice of law).

                  (f) SEVERABILITY. The invalidity or unenforceability of any
provision or provisions of this Agreement shall not affect the validity or
enforceability of any other provision hereof, which shall remain in full force
and effect.

                  (g) ARBITRATION. Subject to Section 7(d), any controversy or
claim arising out of or relating to this Agreement or the breach thereof, or the
Employee's Employment or the termination thereof, shall be settled in Santa
Clara County, California, by arbitration in accordance with the National Rules
for the Resolution of Employment Disputes of the American Arbitration
Association. The decision of the arbitrator shall be final and binding on the
parties, and judgment on the award rendered by the arbitrator may be entered in
any court having jurisdiction thereof. The parties hereby agree that the
arbitrator shall be empowered to enter an equitable decree mandating specific
enforcement of the terms of this Agreement. The Company and the Employee shall
share equally all fees and expenses of the arbitrator; provided, however, that
the Company or the Employee, as the case may be, shall bear all fees and
expenses of the arbitrator and all of the legal fees and out-of-pocket expenses
of the other party if the arbitrator determines that the claim or position of
the Company or the Employee, as the case may be, was without reasonable
foundation. The Employee hereby consents to personal jurisdiction of the state
and federal courts located in the State of California for any action or
proceeding arising from or relating to this Agreement or relating to any
arbitration in which the parties are participants.

                  (h) NO ASSIGNMENT. This Agreement and all rights and
obligations of the Employee hereunder are personal to the Employee and may not
be transferred or assigned by the Employee at any time. The Company may assign
its rights under this Agreement to any entity that assumes the Company's
obligations hereunder in connection with any sale or transfer of all or a
substantial portion of the Company's assets to such entity.

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                           (i) COUNTERPARTS. This Agreement may be executed in
two or more counterparts, each of which shall be deemed an original, but all of
which together shall constitute one and the same instrument.


                  IN WITNESS WHEREOF, each of the parties has executed this
Agreement, in the case of the Company by its duly authorized officer, as of the
day and year first above written.



                                        ---------------------------------------
                                        HYPERION SOLUTIONS CORPORATION


                                        By /s/ John M. Dillon
                                           ------------------------------------

                                        Title: President and CEO
                                              ---------------------------------


                                        Employee:

                                        /s/ Stephen V. Imbler
                                        ---------------------------------------
                                        Stephen V. Imbler


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                                   SCHEDULE A


Alabama                                       New York
Alaska                                        North Carolina
Arizona                                       North Dakota
Arkansas                                      Ohio
California                                    Oklahoma
Colorado                                      Oregon
Connecticut                                   Pennsylvania
Delaware                                      Rhode Island
Florida                                       South Carolina
Georgia                                       South Dakota
Hawaii                                        Tennessee
Idaho                                         Texas
Illinois                                      Utah
Indiana                                       Vermont
Iowa                                          Virginia
Kansas                                        Washington
Kentucky                                      West Virginia
Louisiana                                     Wisconsin
Maine                                         Wyoming
Maryland                                      Australia
Massachusetts                                 Brazil
Michigan                                      Canada
Minnesota                                     England
Mississippi                                   France
Missouri                                      Germany
Montana                                       Hong Kong
Nebraska                                      Israel
Nevada                                        Japan
New Hampshire                                 Mexico
New Jersey                                    Netherlands
New Mexico                                    Singapore
                                              United Kingdom



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