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                                                                   EXHIBIT 10(y)

                              EMPLOYMENT AGREEMENT

          This Employment Agreement (this "Agreement") is dated as of January 1,
2003, between Aon Corporation, a Delaware corporation (the "Company"), and David
P. Bolger (the "Executive").

          WHEREAS, the Company seeks to employ Executive as Executive Vice
President - Finance and Administration of the Company and to have him serve as
senior executive officer of one or more subsidiaries of the Company; and

     WHEREAS, Executive desires to serve and to be employed upon the terms and
subject to the conditions set forth herein.

          NOW, THEREFORE, in consideration of the premises and the mutual
agreements contained herein, the parties hereby agree as follows:

          1.    EMPLOYMENT. The Company hereby agrees to employ the Executive
and the Executive hereby agrees to be employed upon the terms and subject to the
conditions contained in this Agreement. The term of employment of the Executive
pursuant to this Agreement (the "Employment Period") shall commence effective as
of January 8, 2003 (the "Effective Date") and shall end on December 31, 2009,
unless earlier terminated pursuant to Section 4 hereof.

          2.    POSITION AND DUTIES; RESPONSIBILITIES. (a) POSITION AND DUTIES.
The Executive shall be employed as Executive Vice President - Finance and
Administration of the Company and shall, during the Employment Period, be
employed in such position or in such other position or positions with the
Company or subsidiaries of the Company (not inconsistent with the position of
Executive Vice President of the Company) as from time to time determined by the
Chairman and Chief Executive Officer of the Company (the "Chairman and CEO") and
shall report directly to the Chairman and CEO. During the Employment Period, the
Executive shall perform faithfully and loyally and to the best of his abilities
the duties assigned to him hereunder and shall devote his full business time,
attention and effort to the affairs of the Company and its subsidiaries and
shall use his best efforts to promote the interests of the Company and its
subsidiaries. The Executive may engage in charitable, civic or community
activities and, with the prior approval of the Chairman and CEO, may serve as a
director of any other business corporation, provided that (i) such activities or
service do not interfere with his duties hereunder or violate the terms of any
of the covenants contained in Sections 6, 7 or 8 hereof and (ii) such other
business corporation provides the Executive with director and officer insurance
coverage which, in the opinion of the Chairman and CEO, is adequate under the
circumstances.

          (b) RESPONSIBILITIES. Subject to the direction of the Chairman and
CEO, the Executive shall, beginning on April 1, 2003, have authority and
responsibility as Chief Financial Officer of the Company. As of the Effective
Date and continuing for the Employment Period, the Executive shall also have
other executive administrative duties and responsibilities (not inconsistent
with the position of Executive Vice President of the Company) on behalf of the

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Company and its subsidiaries as may from time to time be authorized or directed
by the Chairman and CEO.

          3.    COMPENSATION. (a) BASE SALARY. During the Employment Period, the
Company shall pay to the Executive a base salary at the rate of $750,000 per
annum ("Base Salary"), payable in accordance with the Company's executive
payroll policy. Such Base Salary shall be subject to adjustment at the
discretion of the Chairman and CEO; provided, however, that the Base Salary
shall in no event be less than $750,000 per annum.

          (b) ANNUAL BONUS. During the Employment Period, the Executive shall
participate in the annual incentive bonus plan (the "Senior Executive Plan").
Each such annual incentive bonus shall be determined pursuant to the terms of
the Senior Executive Plan as in effect from time to time; provided, however,
that no such annual incentive bonus shall exceed 150% of the Executive's Base
Salary as in effect at the end of the fiscal year to which such annual incentive
bonus relates; and further provided that for calendar year 2003, Executive's
incentive bonus shall not be less than $582,500.

          (c) STOCK AWARDS. The Executive shall receive a stock award of 100,000
shares of common stock ("Common Stock") of the Company pursuant to the terms of
the Aon Stock Incentive Plan; provided, however, that to the extent such award
remains unvested at the date of termination of employment for any reason other
than Cause as defined in Section 4(c)(ii)(B), (C), (D), or (E), it shall
continue to vest in accordance with its original vesting schedule and the
committee administering such plan shall take such action as shall be necessary
pursuant to the terms of such plan to effect such continued vesting; provided
further that in the event of termination of employment without Cause pursuant to
Section 4(d) hereof, such award shall become immediately vested.

          (d) STOCK OPTIONS. The Executive shall be granted an option for
100,000 shares of the Common Stock of the Company pursuant to the terms of the
Aon Stock Incentive Plan. Such grant shall vest in accordance with the terms of
such plan; provided, however, such grant, to the extent unvested at the date of
termination of employment for any reason other than Cause as defined in Section
4(c)(ii)(B), (C), (D), or (E), shall continue to vest in accordance with its
original vesting schedule; provided further that in the event of termination of
employment without Cause pursuant to Section 4(d) hereof, such option shall
become immediately vested.

          (e) OTHER BENEFITS. During the Employment Period, the Executive shall
be entitled to participate in the Company's employee benefit plans generally
available to executives of the Company (such benefits being hereinafter referred
to as the "Employee Benefits"). The Executive shall be entitled to take time off
for vacation or illness in accordance with the Company's policy for executives
and to receive all other fringe benefits as are from time to time made generally
available to executives of the Company.

          (f) PENSION BENEFITS. (i) Upon termination of employment, the
Executive will be entitled to receive a supplemental pension benefit payable on
a single life annuity basis at age 65, or if later, the date of termination of
employment, which will produce for the Executive aggregate pension benefits
(taking into account the offsets as described in (ii) below), in an annual
amount equal to the aggregate annual pension benefit to which the Executive
would be

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entitled under the Company's qualified and non-qualified defined benefit plans
as in effect on the Effective Date as if Executive's Years of Service (as
defined in the Company's Pension Plan) for benefit calculation purposes is equal
to (i) 10 years plus (ii) the Executive's actual Years of Service with the
Company.

                (ii) the amount of the supplemental pension benefit described in
     Section 3(f)(i) above shall be offset by the benefits provided to Executive
     under any qualified or non-qualified defined benefit plans of the Company.
     The offset described in this paragraph shall be determined on the basis of
     such benefits payable on a single life annuity basis payable at age 65, or
     if later, the date of termination of employment.

                (iii) the Executive may elect to receive the supplemental
     pension benefit in any form available under the qualified or non-qualified
     defined benefit plan of the Company as in effect on the Effective Date, or
     as may be available under any such plan hereafter. For commencement of
     benefits prior to age 65, the supplemental pension benefit will be subject
     to reduction pursuant to the early retirement benefit provisions of the
     Company plans as in effect at the time of payment.

                (iv) if the Executive dies after the Effective Date but before
     the supplemental pension benefit becomes payable, the Executive's spouse
     will be entitled to receive a survivor annuity. The survivor annuity shall
     be payable as of the later of the date of death or the first date the
     Executive would have been entitled to retire and commence a joint and 50%
     survivor annuity (the "Pension Commencement Date"). The amount of the
     survivor annuity shall be equal to the 50% survivor annuity to which the
     spouse is entitled as if: (a) the Executive terminated employment
     immediately before death, (b) the Executive was fully vested in the
     supplemental pension benefit as of such date and (c) the employee survived
     until the Pension Commencement Date, elected to commence the age 65 benefit
     in the form of a joint and 50% survivor annuity as of the Pension
     Commencement Date, and Executive's death occurred on the day after the
     Pension Commencement Date.

          (g) EXPENSE REIMBURSEMENT. During the Employment Period the Company
shall reimburse the Executive in accordance with the Company's policies and
procedures, for all proper expenses incurred by him in the performance of his
duties hereunder.

          4.    TERMINATION. (a) DEATH. Upon the death of the Executive, this
Agreement shall automatically terminate and the Executive's executor,
administrator or designated beneficiary shall be entitled to receive the
Executive's Base Salary which shall have accrued to the date of such death. The
Company shall pay to the Executive's executor or administrator of Executive's
estate a lump sum cash amount equal to the Executive's Base Salary, at the rate
in effect at the date of such death, to which the Executive would have been
entitled from the date of such death until the end of the Employment Period,
reduced by the amount of any benefit paid under any individual or group life
insurance policy maintained by the Company for the benefit of the Executive.

          (b) DISABILITY. The Company may, at its option, terminate this
Agreement upon written notice to the Executive if the Executive, because of
physical or mental incapacity or

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disability, fails to perform the essential functions of his position, with
reasonable accommodation, if relevant, required of him hereunder for a
continuous period of 120 days or any 180 days within any 12-month period. Upon
such termination, the Executive or his legal representative shall be entitled to
receive the Base Salary which shall have accrued to the date of termination,
plus continuation of Base Salary, at the rate in effect at the date of such
termination of employment, until the eighth annual anniversary of the Effective
Date; provided, however, that the amount of any benefit payable under any
disability insurance policy maintained by the Company for the benefit of the
Executive shall be deducted from the payments of such Base Salary, with the
benefit received under such policy reducing the installment of Base Salary
payable closest to the payment of such benefit. In the event of any dispute
regarding the existence of the Executive's incapacity or disability hereunder,
the matter shall be resolved by the determination of an independent physician
agreed to between the Executive and the Board specializing in the claimed area
of incapacity or disability. The Executive shall submit to appropriate medical
examinations for purposes of such determination.

          (c) CAUSE. (i) The Company may at any time, at its option, terminate
the Executive's employment under this Agreement immediately for Cause (as
hereinafter defined). The Company's decision in this regard shall be taken by
the Governance Committee of the Board ("Governance Committee"). The Executive
shall be given at least seven days advanced written notice of any meeting at
which the Governance Committee proposes to put forward for a vote a decision on
whether or not to terminate the Executive for Cause and the written notice shall
describe in reasonable detail the basis on which the Governance Committee may
conclude that Cause exists. The Executive shall have the opportunity to appear
in person and to make such written and/or oral presentation to such meeting of
the Governance Committee as the Executive thinks fit. If a majority of the
Governance Committee authorizes by affirmative vote a termination for Cause at
such meeting (whether or not the Executive makes any oral or written
presentations at such meeting) such determination shall be final and binding
upon the Company and the Executive once such decision is confirmed in writing
and communicated to the Executive.

          (ii) As used in this Agreement, the term "Cause" shall mean any one or
more of the following:

                (A) any failure or inability (other than by reason of physical
     or mental disability determined in accordance with Section 4(b)) of the
     Executive to perform his material duties under this Agreement to the
     satisfaction of at least a majority of the members of the Governance
     Committee, including, without limitation, any refusal by the Executive to
     perform such duties or to perform such specific directives of the Chairman
     and CEO which are consistent with the scope and nature of the Executive's
     duties and responsibilities under this Agreement;

                (B) any intentional act of fraud, embezzlement or theft by the
     Executive in connection with his duties hereunder or in the course of his
     employment hereunder or the Executive's admission or conviction of, or plea
     of nolo contendere to, a felony or of any crime involving moral turpitude,
     fraud, embezzlement, theft or misrepresentation;

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                (C) any gross negligence or willful misconduct of the Executive
     resulting in a loss to the Company or any of its subsidiaries, or damage to
     the reputation of the Company or any of its subsidiaries;

                (D) any breach by the Executive of any one or more of the
     covenants contained in Section 6, 7 or 8 hereof; or

                (E) any violation of any statutory or common law duty of loyalty
     to the Company or any of its subsidiaries.

          (iii) The exercise of the right of the Company to terminate this
Agreement pursuant to this Section 4(c) shall not abrogate the rights or
remedies of the Company in respect of the breach giving rise to such
termination.

          (iv) If the Company terminates the Executive's employment for Cause,
as defined in Section 4(c)(ii)(B), (C), (D) or (E), he shall be entitled to:

                (A) accrued Base Salary through the date of the termination of
     his employment; and

                (B) other Employee Benefits to which the Executive is entitled
     upon his termination of employment with the Company, including regular and
     supplemental retirement and disability benefits, in accordance with the
     terms of the plans and programs of the Company.

          (v) if the Company terminates the Executive's employment for Cause, as
defined in Section 4(c)(ii)(A), he shall be entitled to:

                (A) the payments specified by Sections 4(c)(iv)(A) and (B); and

                (B) the continuation of the Base Salary, at the rate in effect
     at the date of such termination of employment, for a period of two years
     from the date of such termination of employment.

          (d) TERMINATION WITHOUT CAUSE. If, during the Employment Period, the
Company terminates the employment of the Executive hereunder for any reason
other than a reason set forth in Section 4(a), (b) or (c), the Company shall
give the Executive 12 months prior written notice of such termination, and:

          (i) Concurrent with such termination, the Executive shall be entitled
     to receive the payments and benefits specified by Sections 4(c)(iv)(A) and
     (B);

          (ii) The Company shall continue to pay the Executive, until the end of
     the Employment Period, his Base Salary at the rate in effect at the date of
     such termination of employment.

Notwithstanding the foregoing provisions of this Section 4(d), if any payment
specified by this Section 4(d) would not be deductible by the Company for
federal income tax purposes by reason

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of Section 162(m) of the Internal Revenue Code of 1986, as amended (the "Code"),
or any similar or successor statute (excluding Section 280G of the Code), such
payment shall be deferred and the amount thereof (plus earnings thereon in
accordance with the terms of such deferral) shall be paid to the Executive at
the earliest time that such payment shall be deductible by the Company.

          (e) VOLUNTARY TERMINATION. The Executive may voluntarily terminate his
employment with the Company prior to the end of the Employment Period for any
reason. If the Executive voluntarily terminates his employment pursuant to this
Section 4(e), the Executive shall give the Company 12 months prior written
notice and shall be entitled to the payments specified by Sections 4(c)(iv)(A)
and (B).

          5.    FEDERAL AND STATE WITHHOLDING. The Company shall deduct from the
amounts payable to the Executive pursuant to this Agreement the amount of all
required federal, state and local withholding taxes in accordance with the
Executive's Form W-4 on file with the Company, and all applicable federal
employment taxes.

          6.    NONCOMPETITION; NONSOLICITATION. (a) GENERAL. The Executive
acknowledges that in the course of his employment with the Company and Aon
Group, Inc., a Maryland corporation ("Aon Group"), he has and will become
familiar with trade secrets and other confidential information concerning the
Company and its subsidiaries, including Aon Group, and that his services will be
of special, unique and extraordinary value to the Company and its affiliates.

          (b) NONCOMPETITION. The Executive agrees that during the period of his
employment with the Company and for a period of two years thereafter (the
"Noncompetition Period") he shall not in any manner, directly or indirectly,
through any person, firm or corporation, alone or as a member of a partnership
or as an officer, director, stockholder, investor or employee of or consultant
to any other corporation or enterprise or otherwise, engage or be engaged, or
assist any other person, firm, corporation or enterprise in engaging or being
engaged, in any business, in which the Executive was involved or had knowledge,
being conducted by, or contemplated by, the Company or any of its subsidiaries,
including Aon Group, Inc., as of the termination of the Executive's employment
in any geographic area in which the Company or any of its subsidiaries including
Aon Group, Inc. is then conducting such business.

          (c) NONSOLICITATION. The Executive further agrees that during the
Noncompetition Period he shall not in any manner, directly or indirectly, induce
or attempt to induce any employee of the Company or any of its subsidiaries,
including Aon Group, to terminate or abandon his or her employment for any
purpose whatsoever.

          (d) EXCEPTIONS. Nothing in this Section 6 shall prohibit the Executive
from being (i) a stockholder in a mutual fund or a diversified investment
company or (ii) a passive owner of not more than two percent of the outstanding
stock of any class of a corporation, any securities of which are publicly
traded, so long as Executive has no active participation in the business of such
corporation.

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          (e) REFORMATION. If, at any time of enforcement of this Section 6, a
court holds that the restrictions stated herein are unreasonable under
circumstances then existing, the parties hereto agree that the maximum period,
scope or geographical area reasonable under such circumstances shall be
substituted for the stated period, scope or area and that the court shall be
allowed to revise the restrictions contained herein to cover the maximum period,
scope and area permitted by law. This Agreement shall not authorize a court to
increase or broaden any of the restrictions in this Section 6.

          (f) CONSIDERATION; BREACH. The Company and the Executive agree that
the payments to be made, and the benefits to be provided, by the Company to the
Executive pursuant to Section 3 hereof shall be made and provided in
consideration of the Executive's agreements contained in Section 6 hereof. In
the event that the Executive shall breach any provision of Section 6 hereof, the
Company shall be entitled immediately to terminate making all remaining payments
and providing all remaining benefits pursuant to Section 3 hereof and upon such
termination the Company shall have no further liability to the Executive under
this Agreement.

          7.    CONFIDENTIALITY. The Executive shall not, at any time during the
Employment Period or thereafter, make use of or disclose, directly or
indirectly, any (i) trade secret or other confidential or secret information of
the Company or of any of its subsidiaries, including Aon Group, Inc. or (ii)
other technical, business, proprietary or financial information of the Company
or of any of its subsidiaries, including Aon Group, not available to the public
generally or to the competitors of the Company or to the competitors of any of
its subsidiaries, including Aon Group, ("Confidential Information"), except to
the extent that such Confidential Information (a) becomes a matter of public
record or is published in a newspaper, magazine or other periodical available to
the general public, other than as a result of any act or omission of the
Executive, (b) is required to be disclosed by any law, regulation or order of
any court or regulatory commission, department or agency, provided that the
Executive gives prompt notice of such requirement to the Company to enable the
Company to seek an appropriate protective order, or (c) is necessary to perform
properly the Executive's duties under this Agreement. Promptly following the
termination of the Employment Period, the Executive shall surrender to the
Company all records, memoranda, notes, plans, reports, computer tapes and
software and other documents and data which constitute Confidential Information
which he may then possess or have under his control (together with all copies
thereof).

          8.    INVENTIONS. The Executive hereby assigns to the Company his
entire right, title and interest in and to all discoveries and improvements,
patentable or otherwise, trade secrets and ideas, writings and copyrightable
material, which may be conceived by the Executive or developed or acquired by
him during the Employment Period, which may pertain directly or indirectly to
the business of the Company or any of its subsidiaries, including Aon Group. The
Executive agrees to disclose fully all such developments to the Company upon its
request, which disclosure shall be made in writing promptly following any such
request. The Executive shall, upon the Company's request, execute, acknowledge
and deliver to the Company all instruments and do all other acts which are
necessary or desirable to enable the Company or any of its subsidiaries to file
and prosecute applications for, and to acquire, maintain and enforce, all
patents, trademarks and copyrights in all countries.

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          9.    ENFORCEMENT. The parties hereto agree that the Company and its
subsidiaries would be damaged irreparably in the event that any provision of
Section 6, 7 or 8 of this Agreement were not performed in accordance with its
terms or were otherwise breached and that money damages would be an inadequate
remedy for any such nonperformance or breach. Accordingly, the Company and its
successors and permitted assigns shall be entitled, in addition to other rights
and remedies existing in their favor, to an injunction or injunctions to prevent
any breach or threatened breach of any of such provisions and to enforce such
provisions specifically (without posting a bond or other security). The
Executive agrees that he will submit himself to the personal jurisdiction of the
courts of the State of Illinois in any action by the Company to enforce any
provision of Section 6, 7 or 8 of this Agreement.

          10.   SURVIVAL. Sections 6, 7, 8 and 9 of this Agreement shall survive
and continue in full force and effect in accordance with their respective terms,
notwithstanding any termination of the Employment Period.

          11.   NOTICES. All notices and other communications required or
permitted hereunder shall be in writing and shall be deemed given when (i)
delivered personally or by overnight courier to the following address of the
other party hereto (or such other address for such party as shall be specified
by notice given pursuant to this Section 11) or (ii) sent by facsimile to the
following facsimile number of the other party hereto (or such other facsimile
number for such party as shall be specified by notice given pursuant to this
Section 11), with the confirmatory copy delivered by overnight courier to the
address of such party pursuant to this Section 11:

          If to the Company, to:

                Aon Corporation
                200 East Randolph
                Chicago, Illinois 60601
                Attention: Chairman and Chief Executive Officer

          with copies to:

                Aon Corporation
                200 East Randolph
                Chicago, Illinois 60601
                Attention: Chairman of the Governance Committee

                Aon Corporation
                200 East Randolph
                Chicago, Illinois 60601
                Attention: Executive Vice President and Chief Counsel

          If to the Executive, to:

                David P. Bolger
                1710 North Orchard Street

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                Chicago, Illinois  60614

                12.   SEVERABILITY. Whenever possible, each provision of this
Agreement shall be interpreted in such manner as to be effective and valid under
applicable law, but if any provision of this Agreement is held to be invalid,
illegal or unenforceable in any respect under applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability shall not affect
the validity, legality or enforceability of any other provision of this
Agreement or the validity, legality or enforceability of such provision in any
other jurisdiction, but this Agreement shall be reformed, construed and enforced
in such jurisdiction as if such invalid, illegal or unenforceable provision had
never been contained herein.

          13.   ENTIRE AGREEMENT. This Agreement constitutes the entire
agreement and understanding between the parties with respect to the subject
matter hereof and supersedes and preempts any prior understandings, agreements
or representations by or between the parties, written or oral, which may have
related in any manner to the subject matter hereof.

          14.   SUCCESSORS AND ASSIGNS. This Agreement shall be enforceable by
the Executive and his heirs, executors, administrators and legal
representatives, and by the Company and its successors and assigns.

          15.   GOVERNING LAW. This Agreement shall be governed by and construed
and enforced in accordance with the internal laws of the State of Illinois
without regard to principles of conflict of laws.

          16.   AMENDMENT AND WAIVER. The provisions of this Agreement may be
amended or waived only by the written agreement of the Company and the
Executive, and no course of conduct or failure or delay in enforcing the
provisions of this Agreement shall affect the validity, binding effect or
enforceability of this Agreement.

          17.   COUNTERPARTS. This Agreement may be executed in two
counterparts, each of which shall be deemed to be an original and both of which
together shall constitute one and the same instrument.

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

                                  AON CORPORATION

                                  By:
                                     --------------------------------

                                  Title:
                                        -----------------------------


                                  EXECUTIVE:


                                  ----------------------------------
                                               David P. Bolger

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