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                                                                   EXHIBIT 10(a)

                          UNITED HEALTHCARE CORPORATION
                      1998 BROAD-BASED STOCK INCENTIVE PLAN

1. PURPOSE OF PLAN.

     This Plan shall be known as the "United HealthCare Corporation 1998
Broad-Based Stock Incentive Plan" (the "Plan"). The purpose of the Plan is to
aid in maintaining and developing personnel capable of contributing to the
future success of United HealthCare Corporation, a Minnesota corporation (the
"Company"), to offer such personnel additional incentives to put forth maximum
efforts for the success of the business, and to afford them an opportunity to
acquire a proprietary interest in the Company through stock options and other
awards as provided herein. The Plan is intended to be a "broadly-based plan"
within the meaning of the New York Stock Exchange Shareholder Approval Policy.
Options granted under this Plan are not intended to be incentive stock options
within the meaning of Section 422 of the Internal Revenue Code of 1986, as
amended (the "Code"). Other awards granted under this Plan shall be in the form
of stock appreciation rights ("SARs"), restricted stock awards or performance
awards as hereinafter described.

2. STOCK SUBJECT TO PLAN.

     Subject to adjustment as provided in Section 14 hereof and the provisions
of this Section 2, the stock to be subject to options or other awards under the
Plan shall be the Company's authorized shares of common stock, par value $.01
per share (the "Common Shares"). The Common Shares may be either authorized but
unissued shares, or issued shares which have been reacquired by the Company.
Subject to adjustment as provided in Section 14 hereof, the number of Common
Shares as to which options may be granted or awards may be issued hereunder
shall be 11,562,698 Common Shares (the "Initial Common Shares"). Each fiscal
quarter 0.75% of the number of Common Shares which were issued and outstanding
as of the end of the fiscal quarter immediately preceding the then-current
fiscal quarter shall be added to the number of Initial Common Shares that were
available for grant in any preceding fiscal quarter but were not otherwise
granted. If grants or awards lapse, expire, terminate or are canceled prior to
the issuance of Common Shares, or if Common Shares are reacquired by the Company
pursuant to this Plan in connection with payment of the exercise price of
options or awards or satisfaction of tax obligations, such Common Shares will be
available for new grants or awards.

3. ADMINISTRATION OF PLAN.

     (a) Administration of Plan by Committee. The Plan shall be administered by
a committee (the "Committee") of two or more directors of the Company, none of
whom shall be officers or employees of the Company and all of whom shall be
"Non-Employee Directors" with respect to the Plan within the meaning of Rule
16b-3 under the Securities Exchange Act of 1934, as amended (the "Exchange
Act"), and any successor rule. The members of the Committee shall be appointed
by and serve at the pleasure of the Board of Directors.

     (b) Authority of Committee. Subject to the express provisions of the Plan,
the Committee shall have the plenary authority and discretion to: (i) determine
the purchase price of the Common Shares covered by each option, (ii) determine
the employees to whom and the time or times at which options and awards shall be
granted and the number of shares to be subject to each, (iii) determine the form
of payment to be made upon the exercise of an SAR or in connection with
performance awards, either cash, Common Shares or a combination thereof, (iv)
determine the terms of exercise of each option and award, (v) accelerate or
defer the time at which all or any part of an option or award may be exercised,
(vi) amend or modify the terms of any option or award with the consent of the
holder of the optionee or grantee, (vii) interpret the Plan, (viii) prescribe,
amend and rescind rules and regulations relating to the Plan, (ix) determine the
terms and provisions of each option or award agreement under the Plan (any of
which agreements need not be identical), (x) delegate such of its authority
granted herein as it deems is in the best interests of the Company, and (xi)
make all other determinations necessary or advisable for the administration of
the Plan, subject to the exclusive authority of the Board of Directors under
Section 16 herein to amend or terminate the Plan. The Committee's determinations
on the foregoing matters, unless otherwise disapproved by the Board of Directors
of the Company, shall be final and conclusive; provided, however, that the
Committee's determinations with respect to the matters set forth in clauses (ii)
and (iii) above, unless delegated as provided in subsection 3(C)



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below, shall be final and conclusive without any right of disapproval by the
Board of Directors of the Company.

     (c) Grants to Certain Officers and Directors. The Chief Executive Officer
of the Company shall have the authority, as granted by the Committee pursuant to
clause (x) of the preceding subsection, to grant, pursuant to the Plan, options
or other awards to eligible persons who are not considered by the Company as its
officers or directors for purposes of Section 16 of the Exchange Act. The Chief
Executive Officer of the Company shall provide information as to any grants made
pursuant to this subsection to the Committee at its next meeting.

     (d) Action of the Committee. The Committee shall select one of its members
as its Chairperson and shall hold its meetings at such times and places as it
may determine. A majority of its members shall constitute a quorum. All
determinations of the Committee shall be made by not less than a majority of its
members. Any decision or determination reduced to writing and signed by all of
the members of the Committee shall be fully effective as if it had been made by
a majority vote at a meeting duly called and held. The grant of an option or
award shall be effective only if a written agreement shall have been duly
executed and delivered or if notice of such option or award shall have been duly
communicated by and on behalf of the Company following such grant. The Committee
may appoint a Secretary and may make such rules and regulations for the conduct
of its business as it shall deem advisable.

4. ELIGIBILITY; GRANTING OF OPTIONS AND AWARDS.

     (a) Generally. Subject to the provisions of Section 4(b) below, all
full-time and part-time employees of, and consultants and independent
contractors to, the Company or its subsidiaries shall be eligible to receive
options and awards under this Plan.

     (b) Grants of Options and Awards. In determining the persons to whom
options and awards shall be granted and the number of shares subject to each,
the Committee may take into account any factors as the Committee in its
discretion shall deem relevant. A person who has been granted an option or award
under this Plan may be granted additional options or awards under the Plan if
the Committee shall so determine.

     (c) No Right to Employment. Nothing in the Plan or in any agreement
thereunder shall confer on any employee any right to continue in the employ of
the Company or any of its subsidiaries or affect in any way the right of the
Company or any of its subsidiaries to terminate his or her employment at any
time.

5. PRICE.

     The Committee shall determine the option price for options and awards. For
purposes of the preceding sentence and for all other valuation purposes under
the Plan, the fair market value of the Common Shares shall be as reasonably
determined by the Committee by such methods or procedures as shall be
established from time to time by the Committee.

6. TERM.

     Each option and award and all rights and obligations thereunder shall
expire on the date determined by the Committee and specified in the option or
award agreement. The Committee shall be under no duty to provide terms of like
duration for options or awards granted under the Plan. Notwithstanding the
foregoing, the term of options granted under the Plan may not extend more than
fifteen (15) years from the date of grant of such option.

7. EXERCISE OF OPTION OR AWARD.

     (a) Vesting. The Committee shall have full and complete authority to
determine whether an option or award will be exercisable in full at any time or
from time to time during the term thereof, or to provide for the exercise
thereof in installments and upon the occurrence of certain events, such as
termination of employment for any reason, and at such times during the term of
the option or award as the Committee may determine and specify in the option or
award agreement.

     (b) Compliance with Securities Laws. The exercise of any option or award
granted hereunder shall be effective only at such time as the sale of Common
Shares pursuant to such exercise will not violate any state or federal
securities or other laws.

     (c) Notice of Exercise; Payment of Exercise Price. An optionee or grantee
electing to exercise an option or award, or his or her representative, shall
give notice to the Company of such election and of the number of shares subject
to such exercise. The Company will verify the appropriateness of the election
and determine the compensation and related withholding tax amounts. The exercise
amount and applicable taxes shall be tendered either prior to the issuance of
shares pursuant to the exercise or, if such option is exercised pursuant to a
cashless exercise and sale transaction, on or prior to the settlement date of
such transaction. Payment shall be made to the Company in cash (including wire
transfer, bank check, certified check, personal check, or money order), or, at
the discretion of the Committee and as specified by the Committee, by delivering
either (i) Common Shares already owned by the optionee or grantee having a fair
market value as of such date equal to the full purchase price of the shares,
together with any applicable withholding taxes, or (ii) a combination of cash
and such shares; provided, however, that an optionee shall not be entitled to
tender Common Shares pursuant to successive, substantially simultaneous
exercises of options granted under this or any other stock option plan of the
Company. The fair market value of such tendered shares shall be determined as
provided in Section 5 herein. Until such person has been issued the shares
subject to such exercise, he or she shall possess no rights as a shareholder
with respect to such shares.

8. ALTERNATIVE STOCK APPRECIATION RIGHTS.

     (a) Grant. At the time of grant of an option or award under the Plan (or at
any other time), the Committee, in its discretion, may grant a SAR evidenced by
an agreement in such form as the Committee shall from time to time approve. Any
such SAR may be subject to restrictions on the exercise thereof as may be set
forth in the agreement representing such SAR, which agreement shall comply with
and be subject to the following terms and conditions and any additional terms
and conditions established by the Committee that are consistent with the terms
of the Plan.

     (b) Exercise. An SAR shall be exercised by the delivery to the Company of a
written notice which shall state that the holder thereof elects to exercise his
or her SAR as to the number of shares



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specified in the notice and which shall further state what portion, if any, of
the SAR exercise amount (hereinafter defined) the holder thereof requests be
paid to him or her in cash and what portion, if any, is to be paid in Common
Shares of the Company. The Committee promptly shall cause to be paid to such
holder the SAR exercise amount, less any applicable withholding taxes, either in
cash, in Common Shares of the Company, or in any combination of cash and shares
as the Committee may determine. Such determination may be either in accordance
with the request made by the holder of the SAR or in the sole and absolute
discretion of the Committee. The SAR exercise amount is the excess of the fair
market value of one share of the Company's Common Shares on the date of exercise
over the per share exercise price in respect of which the SAR was granted,
multiplied by the number of shares as to which the SAR is exercised. For the
purposes, hereof, the fair market value of the Common Shares shall be determined
as provided in Section 5 herein.

9. RESTRICTED STOCK AWARDS.

     The Committee may grant awards of Common Shares subject to forfeiture and
transfer restrictions. Any restricted stock award shall be evidenced by an
agreement in such form as the Committee shall from time to time approve, which
agreement shall comply with and be subject to the following terms and conditions
and any additional terms and conditions established by the Committee that are
consistent with the terms of the Plan:

     (a) Grant of Restricted Stock Awards. Each restricted stock award made
under the Plan shall be for such number of Common Shares as shall be determined
by the Committee and set forth in the agreement containing the terms of such
restricted stock award. Such agreement shall set forth a period of time during
which the grantee must remain in the continuous employment of the Company in
order for the forfeiture and transfer restrictions to lapse. If the Committee so
determines, the restrictions may lapse during such restricted period in
installments with respect to specified portions of the shares covered by the
restricted stock award. The agreement may also, in the discretion of the
Committee, set forth performance or other conditions that will subject the
Common Shares to forfeiture and transfer restrictions. The Committee may, at its
discretion, waive all or any part of the restrictions applicable to any or all
outstanding restricted stock awards.

     (b) Delivery of Common Shares and Restrictions. At the time of a restricted
stock award, the number of Common Shares awarded thereunder shall be registered
in the name of the grantee. If a certificate representing such shares is issued,
such certificate shall be held by the Company or any custodian appointed by the
Company for the account of the grantee subject to the terms and conditions of
the Plan, and shall bear such a legend setting forth the restrictions imposed
thereon as the Committee, in its discretion, may determine. The grantee shall
have all rights of a shareholder with respect to the Common Shares, including
the right to receive dividends and the right to vote such shares, subject to the
following restrictions: (i) the grantee shall not be entitled to delivery of the
stock certificate, if one is issued, until the expiration of the restricted
period and the fulfillment of any other restrictive conditions set forth in the
restricted stock agreement with respect to such Common Shares; (ii) none of the
Common Shares may be sold, assigned, transferred, pledged, hypothecated or
otherwise encumbered or disposed of during such restricted period or until after
the fulfillment of any such other restrictive conditions; and (iii) except as
otherwise determined by the Committee, all of the shares shall be forfeited and
all rights of the grantee to such shares shall terminate, without further
obligation on the part of the Company, unless the grantee remains in the
continuous employment of the Company for the entire restricted period in
relation to which such Common Shares were granted and unless any other
restrictive conditions relating to the restricted stock award are met. Any
Common Shares, any other securities of the Company and any other property
(except for cash dividends) distributed with respect to the Common Shares
subject to restricted stock awards shall be subject to the same restrictions,
terms and conditions as such restricted Common Shares.

     (c) Termination of Restrictions. At the end of the restricted period and
provided that any other restrictive conditions of the restricted stock award are
met, or at such earlier time as otherwise determined by the Committee, all
restrictions set forth in any agreement relating to the restricted stock award
or in the Plan shall lapse as to the restricted Common Shares subject thereto.
Upon payment by the grantee to the Company of any withholding tax required to be
paid, a stock certificate, if one is requested, for the appropriate number of
Common Shares, free of the restrictions and the restricted stock legend, shall
be delivered to the grantee or his or her beneficiary or estate, as the case may
be.

10. PERFORMANCE AWARDS.

     The Committee is further authorized to grant performance awards. Subject to
the terms of this Plan and any applicable award agreement, a performance award
granted under the Plan (i) may be denominated or payable in cash, Common Shares
(including, without limitation, restricted stock), other securities, other
awards, or other property and (ii) shall confer on the holder thereof rights
valued as determined by the Committee, in its discretion, and payable to, or
exercisable by, the holder of the performance awards, in whole or in part, upon
achievement of such performance goals during such performance periods as the
Committee, in its discretion, shall establish. Subject to the terms of this Plan
and any applicable award agreement, the Committee shall determine the
performance goals to be achieved during any performance period, the length of
any performance period, the amount of any performance award granted, and the
amount of any payment or transfer to be made by the grantee and by the Company
under any performance award.

11. INCOME TAX WITHHOLDING AND TAX BONUSES.

     (a) Income Tax Withholding. In order to comply with all applicable federal,
state or local income tax laws or regulations, the Company may take such action
as it deems appropriate to ensure that all applicable federal, state or local
payroll, withholding, income or other taxes, which are the sole and absolute
responsibility of an optionee or grantee under the Plan, are withheld or
collected from such optionee or grantee prior to his or her receipt of Common
Shares pursuant to the exercise of an option or the satisfaction of the
conditions of any other award. In



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order to assist an optionee or grantee in paying all federal and state taxes to
be withheld or collected upon exercise of an option or award, the Committee may,
in its absolute discretion, permit the optionee or grantee to satisfy such tax
obligation by (i) electing to have the Company withhold a portion of the Common
Shares otherwise to be delivered upon exercise of such option or award with a
fair market value, determined in accordance with Section 5 herein, equal to such
taxes or (ii) delivering to the Company Common Shares other than the shares
issuable upon exercise of such option or award with a fair market value,
determined in accordance with Section 5, equal to such taxes. The election must
be made on or before the date that the amount of tax to be withheld is
determined.

     (b) Tax Bonuses. The Committee shall have the authority, at the time of
grant of an option under the Plan or at any time thereafter, to approve tax
bonuses to designated optionees or grantees to be paid upon their exercise of
options or awards granted hereunder. The amount of any such payments shall be
determined by the Committee but shall not exceed one hundred percent (100%) of
the excess of the fair market value of the shares received upon exercise of an
option or award over the price paid therefor. The Committee shall have full
authority in its absolute discretion to determine the amount of any such tax
bonus and the terms and conditions affecting the vesting and payment thereof.

12. ADDITIONAL RESTRICTIONS.

     The Committee shall have full and complete authority to determine whether
all or any part of the Common Shares of the Company acquired upon exercise of
any of the options or awards granted under the Plan shall be subject to
restrictions on the transferability thereof or any other restrictions affecting
in any manner the optionee's or grantee's rights with respect thereto, but any
such restriction shall be contained in the agreement relating to such options or
awards.

13. NONTRANSFERABILITY.

     No option or award granted under the Plan shall be transferable by an
optionee or grantee, otherwise than by will or the laws of descent or
distribution. Except as otherwise provided in an option or award agreement,
during the lifetime of an optionee or grantee, the option or award shall be
exercisable only by such optionee or grantee. The Committee shall have the
authority to waive the provisions of this Section with respect to any grant of
options under the Plan subject to such terms, conditions or limitations as they
may, in their discretion impose.

14. DILUTION OR OTHER ADJUSTMENTS.

     If there shall be any change in the Common Shares through merger,
consolidation, reorganization, recapitalization, dividend in the form of stock
(of whatever amount), stock split or other change in the corporate structure,
appropriate adjustments in the Plan and outstanding options and awards shall be
made by the Committee. In the event of any such changes, adjustments shall
include, where appropriate, changes in the aggregate number of shares subject to
the Plan, the number of shares and the price per share subject to outstanding
options and awards and the amount payable upon exercise of outstanding awards,
in order to prevent dilution or enlargement of option or award rights.

15. AMENDMENT OR DISCONTINUANCE OF PLAN.

     The Board of Directors may amend or discontinue the Plan at any time. The
Committee, or the Company's Chief Executive Officer as authorized hereunder or
by the Committee, may grant options and awards for the number of shares
authorized by Section 2 herein without further amendment to the Plan increasing
the number of shares authorized for distribution. The Board of Directors shall
not alter or impair any option or award theretofore granted under the Plan
without the consent of the holder of the option or award.

16. TIME OF GRANTING.

     Nothing contained in the Plan or in any resolution adopted or to be adopted
by the Board of Directors or by the shareholders of the Company, and no action
taken by the Committee, the Chief Executive Officer or the Board of Directors
(other than the execution and delivery of an option or award agreement), shall
constitute the granting of an option or award hereunder.

17. EFFECTIVE DATE AND TERMINATION OF PLAN.

     (a) Effective Date of Plan. The Board of Directors approved the Plan on May
13, 1998, which shall be the effective date of the Plan.

     (b) Termination of Plan. Unless the Plan shall have been discontinued as
provided in Section 15 hereof, the Plan shall terminate on May 13, 2008. No
option or award may be granted after such termination, but termination of the
Plan shall not, without the consent of the optionee or grantee, alter or impair
any rights or obligations under any option or award theretofore granted.



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