SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-Q

     X           QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(D)
     _               OF THE SECURITIES EXCHANGE ACT OF 1934

                  FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2002

                                       OR

     _          TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(D)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

                          Commission file number 1-7933

                                 Aon Corporation
                                 ---------------
             (Exact Name of Registrant as Specified in its Charter)

           DELAWARE                                             36-3051915
- -------------------------------                            --------------------
(State or Other Jurisdiction of                            (IRS Employer
Incorporation or Organization)                              Identification No.)



200 E. RANDOLPH STREET, CHICAGO, ILLINOIS                         60601
- ------------------------------------------                      ----------
(Address of Principal Executive Offices)                        (Zip Code)

                         (312) 381-1000
                         --------------
                 (Registrant's Telephone Number)


Indicate  by check  mark  whether  the  Registrant:  (1) has filed  all  reports
required to be filed by Section 13 or 15(d) of the  Securities  and Exchange Act
of 1934  during the  preceding  3 months (or for such  shorter  period  that the
Registrant was required to file such reports),  and (2) has been subject to such
filing requirements for the past 90 days. YES  X   NO
                                              ---     ---

Number of shares of common stock outstanding:

                                                               No. Outstanding
              Class                                             as of 3-31-02
              -----                                             -------------

       $1.00 par value Common                                    272,009,453






                                         PART 1
                                  FINANCIAL INFORMATION
                                     Aon CORPORATION
                 CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION


 (MILLIONS)                                                   AS OF              AS OF
                                                           MARCH 31, 2002    DEC. 31, 2001
                                                         ----------------------------------
                                                                            
 ASSETS                                                   (UNAUDITED)

 INVESTMENTS

   Fixed maturities at fair value                                $ 2,442           $ 2,149

   Equity securities at fair value                                   303               382

   Short-term investments                                          2,615             2,975

   Other investments                                                 635               640

                                                         ----------------   ---------------
       TOTAL INVESTMENTS                                           5,995             6,146


 CASH                                                                569               439


 RECEIVABLES

   Insurance brokerage and consulting
        services                                                   7,543             7,033

   Other receivables                                               1,019               953

                                                         ----------------   ---------------
       TOTAL RECEIVABLES                                           8,562             7,986


 GOODWILL (NET OF ACCUMULATED AMORTIZATION:
             2002 - $ 698; 2001 - $ 698)                           3,856             3,842

 OTHER INTANGIBLE ASSETS (NET OF ACCUMULATED
      AMORTIZATION:  2002 - $ 721; 2001- $ 710)                      229               242

 OTHER ASSETS                                                      3,899             3,731



                                                         ----------------   ---------------
       TOTAL ASSETS                                             $ 23,110          $ 22,386
                                                         ================   ===============

                                                              AS OF             AS OF
                                                           MARCH 31, 2002   DEC. 31, 2001
                                                         ----------------------------------
 LIABILITIES AND STOCKHOLDERS' EQUITY                      (UNAUDITED)

 INSURANCE PREMIUMS PAYABLE                                      $ 8,970           $ 8,233

 POLICY LIABILITIES
   Future policy benefits                                          1,249             1,266
   Policy and contract claims                                      1,006               937
   Unearned and advance premiums and contract fees                 2,109             1,974
   Other policyholder funds                                          766               813
                                                         ----------------  ----------------
       TOTAL POLICY LIABILITIES                                    5,130             4,990

 GENERAL LIABILITIES
   General expenses                                                1,624             1,770
   Short-term borrowings                                             212               257
   Notes payable                                                   1,790             1,694
   Other liabilities                                               1,005             1,071
                                                         ----------------  ----------------
       TOTAL LIABILITIES                                          18,731            18,015


 COMMITMENTS AND CONTINGENT LIABILITIES

 REDEEMABLE PREFERRED STOCK                                           50                50

 COMPANY-OBLIGATED MANDATORILY REDEEMABLE
   PREFERRED CAPITAL SECURITIES OF SUBSIDIARY
   TRUST HOLDING SOLELY THE COMPANY'S JUNIOR
   SUBORDINATED DEBENTURES                                           800               800


 STOCKHOLDERS' EQUITY
   Common stock - $1 par value                                       294               293
   Paid-in additional capital                                      1,655             1,654
   Accumulated other comprehensive loss                             (577)             (535)
   Retained earnings                                               3,117             3,077
   Less - Treasury stock at cost                                    (785)             (786)
          Deferred compensation                                     (175)             (182)
                                                         ----------------  ----------------
       TOTAL STOCKHOLDERS' EQUITY                                  3,529             3,521

                                                         ----------------  ----------------
       TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY               $ 23,110          $ 22,386
                                                         ================  ================


                                     - 2 -




                                                  Aon CORPORATION
                                    CONDENSED CONSOLIDATED STATEMENTS OF INCOME
                                                    (UNAUDITED)

                                                                                     FIRST QUARTER ENDED
                                                                            --------------------------------------
 (millions except per share data)                                                 MARCH 31,             MARCH 31,
                                                                                    2002                  2001
                                                                            ------------------  ------------------
                                                                                                    
 Revenue
    Brokerage commissions and fees ......................................             $ 1,444             $ 1,281
    Premiums and other ..................................................                 535                 508
    Investment income ...................................................                 109                  22
                                                                            ------------------  ------------------
       TOTAL REVENUE ....................................................               2,088               1,811
                                                                            ------------------  ------------------

 EXPENSES
    General expenses . ..................................................               1,463               1,396
    Benefits to policyholders . .........................................                 314                 292
    Interest expense ....................................................                  29                  36
    Amortization of intangible assets (Note 7) ..........................                  11                  39
    Unusual charges- World Trade Center (Note 4).........................                  90                   -
                                                                            ------------------  ------------------
       TOTAL EXPENSES. ..................................................               1,907               1,763
                                                                            ------------------  ------------------

 INCOME BEFORE INCOME TAX AND MINORITY INTEREST .........................                 181                  48
    Provision for income tax . ..........................................                  67                  19
                                                                            ------------------  ------------------
 INCOME BEFORE MINORITY INTEREST. .......................................                 114                  29
    Minority interest - 8.205% trust preferred capital securities .......                 (10)                (10)
                                                                            ------------------  ------------------
 NET INCOME .............................................................             $   104             $    19
                                                                            ==================  ==================
    Preferred stock dividends . .........................................                  (1)                 (1)
                                                                            ------------------  ------------------
 NET INCOME AVAILABLE FOR COMMON STOCKHOLDERS . .........................             $   103             $    18
                                                                            ==================  ==================

 BASIC NET INCOME PER SHARE .............................................             $  0.38             $  0.07
                                                                            ==================  ==================

 DILUTIVE NET INCOME PER SHARE. .........................................             $  0.37             $  0.07
                                                                            ==================  ==================

 CASH DIVIDENDS PER SHARE PAID ON COMMON STOCK . ........................             $ 0.225             $  0.22
                                                                            ==================  ==================

 Dilutive average common and common equivalent shares outstanding .......               276.6               267.9
                                                                            ==================  ==================


See the accompanying notes to the condensed consolidated financial statements.

                                     - 3 -



                                                             AON CORPORATION
                                             CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
                                                               (UNAUDITED)

                                                                                                          FIRST QUARTER ENDED
                                                                                                   ---------------------------------
                                                                                                     MARCH 31,          MARCH 31,
 (millions)                                                                                             2002              2001
                                                                                                   --------------    ---------------
                                                                                                                         
 CASH FLOWS FROM OPERATING ACTIVITIES:
   Net income ..................................................................................         $   104             $   19
   Adjustments to reconcile net income to cash provided by operating activities
        Insurance operating assets and liabilities, net of reinsurance . .......................             (22)                48
        Amortization of intangible assets ......................................................              11                 39
        Depreciation and amortization of property, equipment and software ......................              47                 44
        Income taxes ...........................................................................               4                (20)
        Special and unusual charges and purchase accounting liabilities. .......................              43                 23
        Valuation changes on investments, income on disposals and impairments ..................              10                 76
        Other receivables and liabilities - net ................................................              (6)               103
                                                                                                   --------------    ---------------
            CASH PROVIDED BY OPERATING ACTIVITIES ..............................................             191                332
                                                                                                   --------------    ---------------

 CASH FLOWS FROM INVESTING ACTIVITIES:
   Sale of investments
        Fixed maturities
            Maturities .........................................................................              34                 30
            Calls and prepayments ..............................................................              33                 16
            Sales ..............................................................................             265                365
        Equity securities ......................................................................              65                162
        Other investments ......................................................................              14                135
   Purchase of investments
        Fixed maturities .......................................................................            (650)              (385)
        Equity securities ......................................................................              (3)              (196)
        Other investments ......................................................................              (9)               (32)
   Short-term investments - net ................................................................             337               (180)
   Acquisition of subsidiaries .................................................................             (35)               (44)
   Property and equipment and other - net ......................................................             (56)               (57)
                                                                                                   --------------    ---------------
            CASH USED BY INVESTING ACTIVITIES ..................................................              (5)              (186)
                                                                                                   --------------    ---------------

 CASH FLOWS FROM FINANCING ACTIVITIES:
    Treasury and common stock transactions - net ...............................................              13                 18
    Payments of short-term borrowings - net ....................................................             (43)              (252)
    Issuance of long-term debt .................................................................              96                 15
    Interest sensitive, annuity and investment-type contracts
        Deposits. ..............................................................................               -                  3
        Withdrawals ............................................................................             (59)              (102)
    Cash dividends to stockholders .............................................................             (62)               (58)
                                                                                                   --------------    ---------------
            CASH USED IN FINANCING ACTIVITIES ..................................................             (55)              (376)
                                                                                                   --------------    ---------------

 EFFECT OF EXCHANGE RATE CHANGES ON CASH .......................................................              (1)                (2)
                                                                                                   --------------    ---------------
 INCREASE (DECREASE) IN CASH ...................................................................             130               (232)
 CASH AT BEGINNING OF PERIOD ...................................................................             439              1,118
                                                                                                   --------------    ---------------
 CASH AT END OF PERIOD .........................................................................         $   569            $   886
                                                                                                   ==============    ===============


See the accompanying notes to condensed consolidated financial statements.

                                     - 4 -



NOTES TO THE CONDENSED CONSOLIDATED FINANCIAL STATEMENTS


1.       Statement of Accounting Principles
         ----------------------------------

         The financial  results included in this report are stated in conformity
         with accounting  principles generally accepted in the United States and
         are unaudited but include all normal  recurring  adjustments  which the
         Registrant  ("Aon") considers  necessary for a fair presentation of the
         results for such  periods.  These interim  figures are not  necessarily
         indicative of results for a full year as further discussed below.

         Refer to the consolidated  financial statements and notes in the Annual
         Report  to  Stockholders  for the  year  ended  December  31,  2001 for
         additional  details  of  Aon's  financial   position,   as  well  as  a
         description  of the  accounting  policies  which  have  been  continued
         without  material   change,   except  for  the  adoption  of  Financial
         Accounting  Standard  Board's  (FASB)  Statement  No. 141.  The details
         included  in the notes  have not  changed  except as a result of normal
         transactions  in the interim and the events  mentioned in the footnotes
         below.

         Certain  amounts  in  prior  year's  condensed  consolidated  financial
         statements have been reclassified to conform to the 2002 presentation.


2.       Accounting and Disclosure Changes
         ---------------------------------

         Effective January 1, 2002, Aon adopted FASB Statement No. 142, Goodwill
         and Other Intangible Assets. As a result of adopting Statement No. 142,
         the Company's  goodwill is no longer  amortized.  Pursuant to Statement
         No. 142,  goodwill must be  periodically  tested for impairment and the
         new standard  provides six months to complete  the  impairment  review.
         During the quarter, Aon completed its impairment review which indicated
         that there was no impairment as of January 1, 2002. See note 7.

         Aon also has adopted FASB Statement No. 141, Business Combinations.  In
         accordance with Statement No. 141, other intangible  assets that do not
         meet the criteria for  recognition  apart from  goodwill (as defined by
         Statement  No. 141) are to be  classified  as goodwill upon adoption of
         the statement.  Aon has reclassified $287 million of these intangibles,
         net of accumulated amortization, to goodwill as of January 1, 2002. The
         December  31,  2001  condensed   consolidated  statement  of  financial
         position has been changed to reflect this reclass.

         Aon also adopted FASB Statement No. 144,  Accounting for the Impairment
         or  Disposal  of  Long-Lived  Assets,  effective  January 1, 2002.  The
         adoption of Statement  No. 144 did not have a material  impact on Aon's
         consolidated financial statements.


3.       Spin-Off of Underwriting Business
         ---------------------------------

         In April 2001, Aon's Board of Directors approved, in principle,  a plan
         to  spin-off  its  current  underwriting  businesses  to  Aon's  common
         stockholders,  creating two independent, publicly traded companies. The
         transaction  is subject to final Board  approval and certain  insurance
         regulatory  approvals.  The  spin-off  company  will be named  Combined
         Specialty  Group,  Inc.,  and the spin-off is currently  expected to be
         completed in second  quarter  2002.  On April 11, 2002,  Aon received a

                                     - 5 -


         favorable  private letter ruling from the U.S. Internal Revenue Service
         that  provides,  among other  things,  that Aon's  common  stockholders
         should not owe U.S.  tax on a dividend of shares of Combined  Specialty
         common stock in the spin-off.  In first  quarter 2002,  Aon incurred $5
         million of expenses related to the spin-off.  These expenses,  recorded
         in general expenses in the condensed consolidated statements of income,
         are primarily for outside professional fees.


4.       Unusual Charges
         ---------------

         In the third and fourth  quarter  2001,  Aon  recorded  pretax  unusual
         charges of $68  million net of  insurance  and  reinsurance  recoveries
         related to losses  sustained as result of the  destruction of the World
         Trade Center on September 11, 2001 and the death of 175  employees.  In
         the first  quarter  2002,  Aon recorded a pretax $90 million  allowance
         ($56  million  after tax) for a  potentially  uncollectible  receivable
         related to a previously  disclosed  dispute with reinsurers over claims
         related to the World Trade Center  disaster.  The  allowance,  which is
         reported as an unusual charge in the condensed consolidated  statements
         of income,  was  established  due to an April 2002 court  ruling (in an
         unrelated  case) that may impact the venue for  litigation  between the
         Company and its  reinsurers.  This ruling has impacted Aon's ability to
         reasonably  estimate the probable recovery under the claim, as of March
         31, 2002.  Aon  continues to believe  that its  insurance  underwriting
         subsidiary,   Combined  Insurance  Company  of  America  (CICA),  which
         underwrote  accident insurance for the benefit of Aon's employees,  has
         valid reinsurance.


5.       Comprehensive Income  (Loss)
         ----------------------------

         The components of comprehensive  income (loss), net of related tax, for
         the first quarter ended March 31, 2002 and 2001 are as follows:



                  (millions)                                                        2002                  2001
                                                                                    ----                  ----
                                                                                                
                  Net income                                                   $      104             $        19
                  Net derivative losses                                                (7)                    (12)
                  Net unrealized investment gains (losses)                            (13)                     19
                  Net foreign exchange losses                                         (22)                    (43)
                                                                             -------------------    ------------------
                  Comprehensive income (loss)                                  $       62             $       (17)
                                                                             ===================    ==================



         The components of accumulated other  comprehensive loss, net of related
         tax are as follows:



                                                                                  March 31,             December 31,
                  (millions)                                                        2002                    2001
                                                                                    ----                    ----
                                                                                                 
                  Net derivative losses                                        $       (7)             $        -
                  Net unrealized investment losses                                    (55)                    (42)
                  Net foreign exchange losses                                        (347)                   (325)
                  Net additional minimum pension liability                           (168)                   (168)
                                                                             --------------------    -------------------
                  Accumulated other comprehensive loss                         $     (577)             $     (535)
                                                                             ====================    ===================


                                     - 6 -


6.       Business Segments
         -----------------

         Aon classifies its businesses  into three  operating  segments based on
         the types of services and/or products delivered. There is also a fourth
         non-operating segment, Corporate and Other. The Insurance Brokerage and
         Other Services segment consists primarily of Aon's retail,  reinsurance
         and  wholesale  brokerage  operations,  as  well as  related  insurance
         services, including claims services,  underwriting management,  captive
         insurance company management  services and premium  financing.  Certain
         service  businesses  related to insurance  underwriting  operations are
         also reflected in this segment.  The Consulting  segment is Aon's human
         capital  consulting  organization  which utilizes five major practices:
         employee benefits, compensation, management consulting, outsourcing and
         communications.  The Insurance  Underwriting segment provides specialty
         insurance products  including  supplemental  accident,  health and life
         insurance coverages, extended warranty and other specialty property and
         casualty  insurance  products.  Corporate  and  Other  segment  revenue
         consists primarily of investment income from equity, fixed maturity and
         short-term  investments  that are  assets  primarily  of the  insurance
         underwriting   subsidiaries  that  exceed  policyholders   liabilities.
         Revenues are derived from  investment  income from certain  investments
         (which include  non-income  producing  equities),  valuation changes in
         limited partnership investments,  and income and losses on disposals of
         all securities,  including those pertaining to assets maintained by the
         operating  segments.  Corporate  and  Other  expenses  include  general
         expenses,  administrative  and certain  information  technology  costs,
         interest expense and, in 2001, goodwill amortization.

         Amounts reported in the tables for the four segments,  when aggregated,
         total  to  the  amounts  in  the  accompanying  condensed  consolidated
         financial statements. Revenues are attributed to geographic areas based
         on the location of the resources  producing the revenues.  There are no
         material inter-segment amounts to be eliminated.

         Selected information reflecting Aon's operating segments follows.



First Quarter ended March 31:                 Insurance Brokerage                                                Insurance
(millions)                                     and Other Services                  Consulting                  Underwriting
                                              -------------------                  ----------                  ------------
                                               2002           2001              2002          2001            2002        2001
                                                    ----           ----              ----          ----            ----        ----
Revenue
                                                                                                     
   United States                            $   592       $   541            $   149       $   135         $   412     $   406
   United Kingdom                               229           205                 37            36              79          80
   Continent of Europe                          261           240                 27            22              33          28
   Rest of World                                150           131                 20            19              54          53
- ----------------------------------------- ------------- --------------- -- ------------- ------------- -- ----------- ------------
Total Revenue                               $ 1,232       $ 1,117            $   233       $   212         $   578     $   567
- ----------------------------------------- ------------- --------------- -- ------------- ------------- -- ----------- ------------

Income before income taxes
    excluding unusual and special
    charges                                 $   187       $   196             $     27      $     25        $   69     $    68
Unusual charges - World Trade
   Center                                         -             -                    -             -            90           -
Special charges                                   -            70                    -             1             5           1
- ----------------------------------------- ------------- --------------- -- ------------- ------------- -- ----------- ------------
Income before income taxes                  $   187       $   126             $     27      $     24        $  (26)     $   67
- ----------------------------------------- ------------- --------------- -- ------------- ------------- -- ----------- ------------


                                     - 7 -



Selected information for Aon's non-operating segment follows:



         -----------------------------------------------------------------------------------------------------------------------
         Corporate and Other
         (millions)                               First quarter ended March 31                         2002                2001

         -----------------------------------------------------------------------------------------------------------------------
                                                                                                                  
         Corporate and Other revenue:
         Limited partnership investments                                                               $  9             $  (56)
         Income from marketable equity securities and other
            investments                                                                                   3                  1
                                                                                    --------------------------------------------
         Corporate and Other revenue before one-time items
           and loss on disposals and related expenses                                                    12                (55)
         Interest on tax refund                                                                          48                   -
         Loss on disposals and related expenses *                                                       (15)               (30)
                                                                                    --------------------------------------------
         Corporate and Other revenue                                                                     45                (85)
         Non-operating expenses:
           General expenses                                                                              23                  19
            Interest expense                                                                             29                  36
            Amortization of goodwill                                                                      -                  29
         -----------------------------------------------------------------------------------------------------------------------
         Loss before income tax                                                                        $ (7)            $ (169)
         -----------------------------------------------------------------------------------------------------------------------

<FN>
         *  Includes  impairment  write-downs  of $8 million and $29 million for
            the first quarter ended March 31, 2002 and 2001, respectively.
</FN>



7.       Goodwill and Other Intangible Assets
         ------------------------------------

         In accordance  with FASB  Statement No. 142, all of Aon's goodwill will
         no longer  be  amortized.  Goodwill  and other  intangible  assets  are
         allocated to various reporting units, which are either at its operating
         segments or one reporting level below the operating  segment.  In prior
         years,  goodwill  amortization  has been  expensed in the Corporate and
         Other segment. Statement No. 142 requires Aon to compare the fair value
         of the  reporting  unit to its  carrying  amount on an annual  basis to
         determine if there is  potential  impairment  of goodwill.  If the fair
         value  of the  reporting  unit is less  than  its  carrying  value,  an
         impairment  loss would be recorded to the extent that the fair value of
         the goodwill within the reporting unit is less than the carrying value.
         Fair value is estimated  based on revenue  multiples,  earnings  before
         interest taxes,  depreciation and amortization  (EBITDA) and discounted
         cash flows.

                                     - 8 -


         A  reconciliation  of the prior year's  quarter  reported net income to
         adjusted  net income  had  Statement  No. 142 and the  reclassification
         provisions  of  Statement  No.  141 been  applied as of January 1, 2001
         follows:




         (millions, except per share amounts)                                      Three Months Ended March 31, 2001
                                                                         ------------------------------------------------------
                                                                                             Basic Net        Dilutive Net
                                                                                              Income              Income
                                                                             Amount          Per Share          Per Share
                                                                         ---------------  ---------------  ----------------
                                                                                                   
         Reported net income                                              $         19     $       0.07     $        0.07

         Add back amortization (net of tax):
             Goodwill                                                               25             0.09              0.09
             Intangible assets reclassified to goodwill                              3             0.01              0.01
         Less amortization (net of tax):
             Other intangible assets - change in amortization
                  periods                                                            1                -                 -
                                                                         ---------------  ---------------  ----------------
                                                                          $         46     $       0.17     $        0.17
                                                                         ===============  ===============  ================
         Reported net income and net income per share
             for the three months ended March 31, 2002                    $        104     $       0.38     $        0.37
                                                                         ===============  ===============  ================


The changes in the carrying  amount of goodwill for the quarter  ended March 31,
2002 are as follows:




                                                              Insurance
                                                              Brokerage
    (millions)                                                and Other                         Insurance
                                                               Services       Consulting      Underwriting         Total
                                                               --------       ----------      ------------         -----
                                                                                                      
    Balance as of December 31, 2001 (note 2)                   $ 3,239          $   366           $ 237           $ 3,842
    Goodwill acquired during quarter                                16                1               -                17
    Foreign currency revaluation                                    (3)               -               -                (3)
                                                               ---------        ---------        ---------        ---------
    Balance as of March 31, 2002                               $ 3,252          $   367           $ 237           $ 3,856
                                                               =========        =========        =========        =========


    Amortizable intangible assets by asset class follow:



                                                      Customer           Present Value        Marketing,
    (millions)                                      Related and            of Future          Technology
                                                   Contract Based           Profits           and Other            Total
                                                   --------------          ---------          ----------           -----
                                                                                                       
    Balance as of December 31, 2001                     $ 86                 $ 80                $ 76              $ 242
                                                       ======               ======              ======            =======
    Balance at March 31, 2002                           $ 82                 $ 75                $ 72              $ 229
                                                       ======               ======              ======            =======

    Range of years amortized                           3 - 29               4 - 13              3 - 25
                                                       ======               ======              ======


Amortization  expense  for  amortizable  intangible  assets for the years  ended
December 31, 2002, 2003, 2004, 2005 and 2006 is estimated to be $46 million, $45
million, $42 million, $40 million and $38 million, respectively.

                                     - 9 -



8.       Capital Stock
         -------------

         During first quarter 2002, Aon issued or reissued  1,749,000  shares of
         common  stock  for  employee   benefit  plans  and  144,000  shares  in
         connection with the employee stock purchase plan. Aon purchased  74,000
         shares of its common stock at a total cost of $2.9 million during first
         quarter  2002.  There were 22.4 million  shares of common stock held in
         treasury  at  March  31,  2002,  of which  all but  67,000  shares  are
         restricted as to their reissuance.


9.       Capital Securities
         ------------------

         In 1997, Aon Capital A, a subsidiary  trust of Aon, issued $800 million
         of 8.205% mandatorily  redeemable preferred capital securities (capital
         securities).  The sole asset of Aon Capital A is $824 million aggregate
         principal  amount  of  Aon's  8.205%  Junior  Subordinated   Deferrable
         Interest Debentures due January 1, 2027.


10.      Business Combinations
         ---------------------

         For the  first  quarter  2002,  Aon  made  payments  of $2  million  on
         restructuring  charges and purchase accounting  liabilities relating to
         business combinations.

         In 1996 and 1997, Aon recorded  pretax  special  charges of $60 million
         and $145 million, respectively, related to management's commitment to a
         formal plan of restructuring Aon's brokerage  operations as a result of
         the acquisition of Alexander & Alexander Services,  Inc. (A&A). Also in
         1997,   following   management's   commitment   to  a  formal  plan  of
         restructuring the A&A and Bain Hogg brokerage operations,  Aon recorded
         $264  million in costs to  restructure  those  acquisitions.  Together,
         these  costs were  primarily  related to  termination  benefits of $152
         million,  lease abandonments and other exit costs of $280 million,  and
         asset  impairments of $37 million.  All termination  benefits have been
         paid. The remaining  liability of $55 million is for lease abandonments
         and other exit costs.

         The  following  table  sets forth  recent  activity  relating  to these
         liabilities:

                  (millions)
                  Balance at December 31, 2000                      $        78
                  Cash payments in 2001                                     (19)
                  Cash payments in 2002                                      (2)
                  Foreign currency revaluation                               (2)
                                                                    ------------
                  Balance at March 31, 2002                         $        55
                                                                    ============

         All of Aon's unpaid liabilities  relating to acquisitions are reflected
         in general expense liabilities in the condensed consolidated statements
         of financial position.

                                     - 10 -


11.      Business Transformation Plan
         ----------------------------

         In fourth  quarter 2000,  Aon announced a formal plan of  restructuring
         Aon's  worldwide  operations.   This  plan  constitutes  the  "business
         transformation  plan" and will  continue  into 2002.  Costs of the plan
         include  special charges and transition  costs.  Pretax charges of $300
         million  were  recorded  in 2001 and  2000,  of which $72  million  was
         recorded in first quarter 2001, and are recorded in general expenses in
         the condensed consolidated statements of income. The special charges in
         the first quarter 2001 included costs related to  termination  benefits
         of $23 million, other costs to exit an activity of $3 million and other
         charges of $46 million primarily  relating to costs for the abandonment
         of  systems  and  equipment,  as well as to end  Aon's  involvement  in
         certain joint ventures and service partner  relationships  that did not
         meet profitability hurdles.

         Approximately 4,000 employees have either departed  voluntarily or have
         positions  that have been  eliminated.  Most of the  terminations  have
         occurred and are related to the Insurance  Brokerage and Other Services
         segment in the U.S. and the U.K.

         For the first quarter 2002, Aon made payments of $9 million  related to
         the business transformation plan.

         The  following  table sets forth the activity  related to the liability
         for termination benefits and costs to exit an activity:



                                                                                              Other Costs
                                                                        Termination            to Exit an
           (millions)                                                      Benefits              Activity                Total
           --------------------------------------------------------------------------------------------------------------------

                                                                                                           
           Expense charged in 2000                                     $       54              $      6             $      60
           Cash payments in 2000                                              (13)                   (3)                  (16)
           Expense charged in 2001                                            109                    21                   130
           Cash payments in 2001                                              (73)                  (20)                  (93)
           Cash payments in 2002                                               (8)                   (1)                   (9)
           Foreign currency revaluation                                        (2)                    -                    (2)
           --------------------------------------------------------------------------------------------------------------------
           Balance at March 31, 2002                                   $       67              $      3             $      70
           --------------------------------------------------------------------------------------------------------------------


         All of Aon's  unpaid  liabilities  relating to business  transformation
         plan are  reflected in general  expense  liabilities  in the  condensed
         consolidated statements of financial position.

                                     - 11 -


12.      Income Per Share
         ----------------

         Income per share is calculated as follows:



                                                                                   First Quarter Ended March 31,
                                                                     ---------------------------------------------------
                (millions except per share data)                                  2002                       2001
                --------------------------------------------------------------------------------------------------------

                                                                                                    
                Net income                                                      $  104                     $   19
                Redeemable preferred stock dividends                                (1)                        (1)
                                                                      --------------------------------------------------
                Net income  for dilutive and basic                              $  103                     $   18
                                                                      ==================================================

                Basic shares outstanding                                           274                        265
                Common stock equivalents                                             3                          3
                                                                      --------------------------------------------------
                Dilutive potential common shares                                   277                        268
                --------------------------------------------------------------------------------------------------------
                Basic net income per share                                    $   0.38                   $   0.07
                Dilutive net income per share                                 $   0.37                   $   0.07
                --------------------------------------------------------------------------------------------------------



13.      Alexander & Alexander Services Inc. (A&A) Discontinued Operations
         -----------------------------------------------------------------

         Prior to its  acquisition  by Aon,  A&A  discontinued  its property and
         casualty insurance underwriting  operations in 1985, some of which were
         then  placed  into  run-off,  with  the  remainder  sold  in  1987.  In
         connection with those sales, A&A provided  indemnities to the purchaser
         for various estimated and potential  liabilities,  including provisions
         to cover future losses attributable to insurance pooling  arrangements,
         a stop-loss  reinsurance  agreement and actions or omissions by various
         underwriting agencies previously managed by an A&A subsidiary.

         In  January  2002,  Aon  settled  certain  of  these  liabilities.  The
         settlements  had  no  material  effect  on the  condensed  consolidated
         financial statements.  As of March 31, 2002, the liabilities associated
         with the foregoing  indemnities  were included in other  liabilities in
         the condensed consolidated statements of financial position.  These A&A
         related  liabilities  amounted  to  $73  million,  net  of  reinsurance
         recoverables and other assets of $86 million.


14.      Contingencies
         -------------

         Aon  and  its  subsidiaries   are  subject  to  numerous  claims,   tax
         assessments and lawsuits that arise in the ordinary course of business.
         The damages  that may be claimed  are  substantial,  including  in many
         instances  claims for punitive or extraordinary  damages.  Accruals for
         these  items have been  provided  to the extent  that losses are deemed
         probable and are estimable.

         In the second quarter of 1999,  Allianz Life Insurance Company of North
         America,  Inc.  ("Allianz")  filed an amended  complaint  in  Minnesota
         adding a brokerage  subsidiary of Aon as a defendant in an action which
         Allianz brought against three insurance  carriers reinsured by Allianz.
         These three carriers  provided  certain types of workers'  compensation
         reinsurance to a pool of insurers and to certain  facilities managed by
         Unicover  Managers,  Inc.  ("Unicover"),  a New Jersey  corporation not
         affiliated with Aon.  Allianz alleges that the Aon subsidiary  acted as
         an agent of the three  carriers  when placing  reinsurance  coverage on
         their behalf.  Allianz claims that the  reinsurance it issued

                                     - 12 -


         should be  rescinded  or that it should be  awarded  damages,  based on
         alleged fraudulent,  negligent and innocent  misrepresentations  by the
         carriers, through their agents, including the Aon subsidiary defendant.
         Aon believes that the Aon subsidiary has  meritorious  defenses and the
         Aon subsidiary intends to vigorously defend this claim.

         Except for an action  filed to compel Aon to produce  documents,  which
         has  been  settled,   the  Allianz  lawsuit  is  the  only  lawsuit  or
         arbitration  relating to Unicover  in which any  Aon-related  entity is
         currently a party.

         Certain U.K. subsidiaries of Aon have been required by their regulatory
         body, the Personal  Investment  Authority (PIA), to review advice given
         by those  subsidiaries  to individuals  who bought pension plans during
         the period from April 1988 to June 1994. These reviews have resulted in
         a requirement to pay compensation to clients based on guidelines issued
         by the PIA.  Aon's  ultimate  exposure  from the private  pension  plan
         review,  as  presently  calculated,  is subject to a number of variable
         factors including, among others, general level of pricing in the equity
         markets,  the  interest  rate  established  quarterly  for  calculating
         compensation,  and the precise scope,  duration and  methodology of the
         review,  including whether recent  regulatory  guidance will have to be
         applied to previously settled claims.

         One of Aon's  insurance  subsidiaries is a defendant in twelve lawsuits
         in  Mississippi.  The  lawsuits  generally  allege  misconduct  by  the
         subsidiary  in  the  solicitation  and  sale  of  insurance   policies.
         Attorneys  representing  the  plaintiffs in these lawsuits have advised
         the  subsidiary  that  approximately  1,800  other  current  or  former
         policyholders may file similar claims.  The attorneys have furnished no
         or only sparse details of these possible claims. Each lawsuit includes,
         and each  threatened  claim  could  include,  a  request  for  punitive
         damages.  Each suit and any  threatened  claim that matures into a suit
         will be most vigorously defended.

         Although the ultimate  outcome of all matters  referred to above cannot
         be ascertained and liabilities in indeterminate  amounts may be imposed
         on Aon or  its  subsidiaries,  on the  basis  of  present  information,
         amounts already provided, availability of insurance coverages and legal
         advice  received,  it is the opinion of management that the disposition
         or  ultimate  determination  of such  claims  will not have a  material
         adverse effect on the consolidated  financial position of Aon. However,
         it is possible that future  results of operations or cash flows for any
         particular  quarterly or annual period could be materially  affected by
         an unfavorable resolution of these matters.

                                     - 13 -

                                 AON CORPORATION
                      MANAGEMENT'S DISCUSSION AND ANALYSIS
                OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

                       FIRST QUARTER ENDED MARCH 31, 2002


GENERAL
- -------

Aon has three  operating  segments:  Insurance  Brokerage  and  Other  Services,
Consulting and Insurance  Underwriting.  These segments are based on the type of
client and the services or products delivered.  Aon has a fourth,  non-operating
segment, Corporate and Other.

References  to  organic  revenue  growth  exclude  the  impact of  acquisitions,
dispositions,  transfers,  investment income, foreign exchange and other unusual
items. Within the Insurance Underwriting segment, written premiums are the basis
for the  measurement of organic  growth.  References to income before income tax
are before  minority  interest  related to the  issuance  of 8.205%  mandatorily
redeemable  preferred  capital  securities.  For purposes of  operating  segment
discussions,  comparisons  against  2001  results  exclude  unusual  and special
charges.

INFORMATION CONCERNING FORWARD-LOOKING STATEMENTS
- -------------------------------------------------

This quarterly report may contain certain statements relating to future results,
which are  forward-looking  statements  as that term is defined  in the  Private
Securities Litigation Reform Act of 1995. These  forward-looking  statements are
subject to certain risks and  uncertainties  that could cause actual  results to
differ materially from either historical or anticipated results,  depending on a
variety of factors.  Potential  factors  that could impact  results  include the
general   economic   conditions  in  different   countries   around  the  world,
fluctuations  in global equity and fixed income  markets,  changes in commercial
property and casualty  premium rates,  the competitive  environment,  the actual
cost of  resolution  of  contingent  liabilities,  the  final  execution  of the
business transformation plan, the ultimate cost and timing of the implementation
thereof, the actual cost savings and other benefits resulting therefrom, whether
the Company  ultimately  implements  the proposed  spin-off of its  underwriting
operations,  rating agency actions,  and any proposed capital  raising,  and the
timing and terms associated therewith,  and events surrounding terrorist attacks
of September 11, 2001,  including the timing and resolution of related insurance
and reinsurance issues.

SPIN-OFF OF UNDERWRITING BUSINESS
- ---------------------------------

As previously  disclosed,  on April 20, 2001, Aon's Board of Directors approved,
in principle, a plan to spin-off its insurance underwriting  businesses to Aon's
common stockholders,  creating two independent,  publicly traded companies.  The
spin-off  would take the form of a tax-free  stock  dividend of the  outstanding
shares of common stock of Combined Specialty Group, Inc. (Combined Specialty), a
new  company  formed  to  hold  the  insurance  underwriting   businesses.   The
transaction  requires  final Board  approval  and certain  insurance  regulatory
approvals and is currently  expected to be completed in second  quarter 2002. On
April 11, 2002,  Aon received a favorable  private  letter  ruling from the U.S.
Internal  Revenue Service that provides,  among other things,  that Aon's common
stockholders  should  not owe U.S.  tax on a  dividend  of  shares  of  Combined
Specialty common stock in the spin-off.

In the first  quarter 2002,  Aon incurred $5 million of expenses  related to the
spin-off.  These  expenses,  recorded  in  general  expenses  in  the  condensed
consolidated statements of income, are primarily for outside professional fees.

                                     - 14 -


BUSINESS TRANSFORMATION PLAN
- ----------------------------

In fourth quarter 2000, Aon began a comprehensive  business  transformation plan
designed  to  enhance  client  service,  improve  productivity  through  process
redesign, and accelerate organic revenue growth. The implementation of this plan
began in the fourth quarter of 2000 and, due to delays as discussed below,  will
continue  into 2002.  The  majority of the plan costs and savings are related to
the Insurance Brokerage and Other Services segment,  principally in the U.S. and
the United  Kingdom,  where most of Aon's  offices and  employees  are  located.
Outside of U.S. retail brokerage, the business transformation plan has delivered
expected benefits of improved revenue growth and enhanced  productivity.  In the
U.S. retail brokerage,  however,  a more extensive plan involved the redesign of
many  processes and job roles,  which  resulted in delays  implementing  certain
process  conversions.  The conversion of all large account back office servicing
in U.S.  retail  brokerage to the four regional  services  centers was completed
during the first quarter.  Small account back office  servicing in the U.S. will
be  converted  by the end of second  quarter  2002.  The delays have been due to
challenges in handling higher volumes of transfers  between field operations and
the client service  business  units as well as the  destruction of Aon's largest
and most advanced  client service  business unit,  which was housed in the World
Trade  Center.  This delay also  adversely  affected new business  production as
attention  was  diverted  from  generating  new  accounts to  completing  client
conversions.  Expenses have been higher than expected, due in part to additional
temporary employee expense necessary to complete the account  conversions to the
client service  business  units, as well as increased  compensation  for certain
brokerage  employees and the hiring of employees with  specialized  skills.  The
changing  dynamics of the  insurance  marketplace  have also  increased the time
requirements for handling certain job functions.

In connection  with the plan, Aon recorded pretax special charges of $72 million
($44 million after tax or $0.16 per share) in first quarter 2001. Pretax charges
of $23  million in first  quarter  2001  related  to  termination  benefits  and
involved  about 1,200  employees.  As part of the business  transformation,  Aon
examined its  marginal  return  non-core  business  alliances  and took a pretax
charge of $38 million to end Aon's  involvement  in certain  joint  ventures and
service partner  relationships that did not meet profitability  hurdles. It also
allowed Aon to further reduce  headcounts.  Charges of $11 million were incurred
for asset  impairments,  primarily  relating to the  abandonment  of systems and
equipment, and other charges.

Net transition costs,  primarily related to our core operating businesses,  were
approximately $3 million for both the first quarter 2002 and 2001, respectively,
and consisted of process conversion costs, consulting fees and temporary help.

Annualized  pretax savings from the plan,  which is not fully  implemented,  are
estimated to be  approximately  $150 million  related to actions  already taken.
These  savings are  expected to be  achieved  starting in 2002 on an  annualized
basis  as  transition   and  other   one-time  costs  related  to  the  business
transformation  plan are eliminated.  These savings will be partially  offset by
increased  compensation  for certain U.S. retail employees and the hiring of new
employees with special  skills at higher  compensation  levels.  Savings in both
2002  and 2001 in the U.S.  were  substantially  offset  by lower  revenues  and
transition costs related in part to longer than expected duplicate processing.

                                     - 15 -


CONSOLIDATED RESULTS
- --------------------

Total revenue increased $277 million or 15% when compared to first quarter 2001.
Excluding  the effect of foreign  exchange  rates,  revenues rose 18% over first
quarter 2001,  attributable  principally to growth in brokerage  commissions and
fees and an increase in reported  investment income.  Investment income improved
year over year due to a one-time  tax related  item of $48  million,  a positive
valuation change in limited  partnerships in 2002 versus reduced valuations last
year, and lower impairment  writedowns this year.  Consolidated  revenue for the
operating segments grew approximately 14% on an organic basis over last year.

Brokerage  commissions  and fees  increased $163 million or 13% in first quarter
2002. This  improvement was primarily from organic growth,  including the impact
of  increased  premium  rates,   increased  new  business,   and  2001  business
combination  activity,  especially  ASI Solutions  Incorporated  (ASI) and First
Extended, Inc.

 Premiums and other is primarily related to insurance  underwriting  operations.
Premiums and other  improved $27 million over first  quarter  2001. In the first
quarter,  growth in the accident and health lines and new specialty property and
casualty  lines  was  somewhat  offset by the  impact of the prior  loss of some
accounts in the warranty business.

Investment  income,  which  includes  related  expenses  and  income  or loss on
disposals and  impairments,  increased  significantly  in the first quarter 2002
when  compared to prior year,  of which $48 million of the increase was due to a
tax related  settlement.  In December  2001,  Aon sold the vast  majority of its
limited partnership (LP) portfolio.  The remaining LP's posted a positive change
in valuation versus reduced valuations in 2001. Also,  impairment writedowns for
certain directly owned equity  investments were $21 million less than last year.
These  improvements  were somewhat  offset by lower returns due to reductions in
short-term interest rates from 2001.  Investment income from Insurance Brokerage
and Other  Services and  Consulting  segments,  primarily  relating to fiduciary
funds,  decreased $26 million in first quarter 2002 compared to 2001,  primarily
as a result of declines in rates.

Total expenses increased $144 million or 8% over first quarter 2001. Expenses in
2002 include $5 million of costs related to the spin-off of Combined  Specialty,
as well as an unusual  charge of $90 million,  to  establish an allowance  for a
potentially  uncollectible  receivable related to a dispute with reinsurers over
claims  related  to the World  Trade  Center.  In 2001,  $72  million of special
charges were recognized for the business  transformation  plan.  Total expenses,
excluding these charges,  rose 7%. General expenses  increased $67 million or 5%
in the quarter  reflecting growth of the businesses and higher costs in the U.S.
retail brokerage  business.  Benefits to  policyholders  rose $22 million or 8%.
Interest expense declined $7 million or 19%, driven by lower short-term interest
rates.  Amortization  of intangible  assets declined $28 million as goodwill was
not amortized in 2002, in accordance with FAS 142 (see notes 1 and 7).

As a result of these  factors,  income before income tax improved  significantly
from $48 million in 2001 to $181 million in 2002.

First  quarter 2002 net income rose to $104 million  ($0.37 per dilutive  share)
compared to $19 million ($0.07 per dilutive share) in 2001. Basic net income per
share  was  $0.38  and  $0.07 in first  quarter  2002  and  2001,  respectively.
Dividends on the redeemable  preferred  stock have been deducted from net income
to compute  income per share.  The  exclusion of goodwill  amortization  in 2002
contributed  to Aon's  effective tax rate  declining to 37% in the first quarter
2002 from 39% in 2001.

                                     - 16 -



OPERATING SEGMENTS
- ------------------

INSURANCE BROKERAGE AND OTHER SERVICES
- --------------------------------------

The Insurance Brokerage and Other Services segment consists principally of Aon's
retail,  reinsurance  and  wholesale  brokerage  operations  as well as  related
insurance services, including claims services,  underwriting management, captive
insurance  company  management  services  and premium  financing.  This  segment
represented 59% of Aon's total revenues for the first quarter of 2002.

First  quarter 2002  Insurance  Brokerage  and Other  Services  revenue was $1.2
billion, up 10% over last year.  Excluding foreign exchange,  revenues rose 12%.
Organic  revenue  growth was 13% in the  quarter,  up from 8% in fourth  quarter
2001.  Claims  services,  domestic,  international  and wholesale  brokerage all
posted solid revenue gains for the quarter. Reported revenues were impacted by a
decline in investment  income of $25 million due to a drop in interest rates. In
addition,  the managing underwriting business experienced a temporary decline in
revenue due to a required change in an insurance  carrier  relationship  that is
expected to be corrected during the second quarter.

U.S. revenue of $592 million for the quarter was up 9% from 2001, despite a fall
off of investment  income due to lower  interest  rates.  The increase  reflects
fundamental  growth,  improved  pricing and the impact of  acquisitions,  all of
which  more  than  offset  the  direct  and  indirect  impact  of  the  business
transformation  plan on the U.S.  retail  operation  and the World Trade  Center
disaster.  International,  reinsurance and wholesale  brokerage  performed well.
U.S.  retail's new to lost business  ratio improved over the fourth quarter 2001
in certain U.S. retail  brokerage units as operational  changes were implemented
to achieve long-term benefits of the business  transformation  plan.  Commercial
property and  casualty  premium  rate  increases  were evident for most lines of
coverage and client  demand for risk  retention  programs and services has risen
along with the upward  trend in premium  rates.  U. K. and  Continent  of Europe
revenues  of $490  million  for the  first  quarter  increased  10%  from  2001,
primarily due to organic growth driven by higher insurance premium rates and new
business.  The reported revenue growth was unfavorably impacted by the effect of
foreign exchange rates.  Rest of world revenue increased $19 million or 15% over
first quarter 2001 reflecting  solid organic growth resulting from new business,
good renewal rates and the positive impact of hardening insurance markets.

Pretax  income was $187 million for the first quarter  2002.  Excluding  special
charges last year pertaining to the business  transformation plan, pretax income
fell 5% from 2001. Pretax margins,  excluding the special charges, were 15.2% in
the quarter compared to 17.5% in 2001. The margin decline was principally driven
by the  significant  decrease in investment  income from last year. In addition,
higher costs in certain parts of the U.S. retail business,  due to delays in the
business  transformation  process,  including  expense to run  parallel  systems
longer than expected,  along with increased compensation costs, including higher
pension costs,  contributed to the margin decline.  These items more than offset
strong organic growth and business transformation savings.


CONSULTING
- ----------

The  consulting  segment  provides  a full  range  of human  capital  management
services.  These services are delivered to a predominately  corporate  clientele
utilizing  five   practices:   employee   benefits,   compensation,   management
consulting,  outsourcing and  communications.  This segment accounted for 11% of
Aon's total revenues for the first quarter 2002.

                                     - 17 -


First quarter 2002 revenue increased 10% to $233 million.  Excluding the foreign
exchange rate impact,  revenues  grew 11%. For the first  quarter 2002,  revenue
grew 4% on an organic basis reflecting slower economic  conditions.  On a global
basis,  the  improvement  in revenue was  influenced  by  acquisition  activity,
especially the inclusion of ASI, acquired in the second quarter 2001, as well as
organic growth. Client demand for solutions that enhance workforce  productivity
continued.  However,  the  worsening  economy  has put some  pressure on organic
revenue growth.

For the  quarter,  U.S.  revenue  of $149  million  was up 10%  from  2001.  The
improvement  primarily  reflects  the impact of the ASI  acquisition.  U.K.  and
Continent of Europe  revenue  rose $6 million for the quarter  compared to 2001.
Organic  revenue  growth and  acquisitions  were somewhat  offset by unfavorable
foreign  exchange rates.  Rest of World revenue rose $1 million from 2001 to $20
million.

Pretax  income was $27 million for the quarter,  a 13% increase  over last year.
Excluding  2001 special  charges,  pretax income  improved 8% over 2001.  Pretax
margins  in this  segment,  excluding  the  special  charges,  were 11.6% in the
quarter compared to 11.8% in 2001. Margin comparisons were positively influenced
during the quarter by strong results in the U.S.  employee benefits business but
were pressured by the effects of a weak economy.


INSURANCE UNDERWRITING
- ----------------------

The Insurance Underwriting segment provides supplemental accident and health and
life insurance coverage through several distribution networks, most of which are
directly  owned by Aon's  subsidiaries,  and  specialty  property  and  casualty
insurance, including extended warranty products. This segment represented 28% of
Aon's total revenues for the first quarter 2002.

Revenue was $578 million in the first quarter 2002, an increase of 2% from 2001.
Excluding  the  impact of  exchange  rates,  revenues  rose 5% for the  quarter.
Improvement   over  last  year  reflects  the  impact  of  organic   growth  and
acquisitions. Organic revenue growth, based on written premiums, was 18% for the
quarter,  due in part to new  specialty  property  and casualty and accident and
health  insurance  business.  Partially  offsetting core business growth was the
prior loss of several  accounts in the extended  warranty  business,  as well as
lower investment income.

U.S.  revenue  increased $6 million in the first  quarter 2002 to $412  million.
Higher  revenues  reflect new product  initiatives  and  increased  revenues for
accident  and health  products,  which more than offset a decline in  electronic
warranty  products.  U.K.  and  Continent  of  Europe  revenue  of $112  million
increased 4% during the quarter due to increased  electronic  warranty business.
Rest of World revenue was $54 million for the first quarter,  up $1 million from
2001.

The pretax  loss was $26  million  for the  quarter.  Excluding  this  quarter's
establishment  of a  $90  million  allowance  for  a  potentially  uncollectible
receivable related to a dispute with reinsurers over claims related to the World
Trade Center and spin-off  related  expenses of $5 million,  and 2001's  special
charge,  pretax  income  rose 1% over last  year.  Before  unusual  and  special
charges,  pretax  margins in this segment were 11.9% in the quarter  compared to
12.0% in 2001.  A decline in  investment  income,  due mainly to lower  interest
rates, affected margin comparisons in the quarter. New underwriting  initiatives
drove premium growth but also resulted in increased  benefits to  policyholders,
which offset an unusual  increase in warranty  claims  during the first  quarter
2001 related to an isolated program that did not affect subsequent quarters.

                                     - 18 -


NON-OPERATING SEGMENT
- ---------------------

CORPORATE AND OTHER
- -------------------

Revenue in this  category  consists  primarily of investment  income  (including
income or loss on disposals, including impairment losses) which is not otherwise
reflected in the results of the operating segments.  Invested assets and related
investment income not directly  required to support the insurance  brokerage and
consulting  businesses,  together with the assets in excess of net  policyholder
liabilities of the underwriting  businesses and related income, are allocated to
the Corporate and Other segment.  Corporate and Other expenses encompass general
expenses, which include administrative and certain information technology costs,
interest expense and, in 2001, goodwill amortization.

Corporate and Other revenue for the first quarter 2002 was $45 million, versus a
negative $85 million in the first quarter 2001. In December  2001,  Aon sold the
vast majority of its limited  partnership  (LP)  portfolio to a special  purpose
entity  (PEPS I). The  remaining  LP's  provided a positive  change in valuation
versus reduced  valuations in 2001.  Also in 2002, Aon recognized $48 million of
interest  income  due to  settlement  of a prior  year tax  related  issue.  The
year-to-year  comparison  is also  impacted  by  lower  write-downs  of  certain
directly-owned equity investments compared to first quarter 2001.

Corporate and Other expenses for the quarter were $52 million,  down $32 million
from the same period last year.  Goodwill  amortization  was $29 million for the
first quarter 2001. In accordance  with  Statement No. 142, which Aon adopted on
January 1, 2002, Aon will no longer  amortize  goodwill.  However,  it will test
annually for impairments.  Interest expense declined $7 million for the quarter,
reflecting  lower interest  rates.  General  expenses rose $4 million over first
quarter 2001 due in part to expenses to establish new  management  personnel for
Combined Specialty.

The revenue and expense  comparisons  discussed above contributed to the overall
Corporate  and Other  pretax loss of $7 million in the quarter  versus a loss of
$169 million last year.

                                     - 19 -


                        CASH FLOW AND FINANCIAL POSITION
                        AT THE END OF FIRST QUARTER 2002



Cash flows from operating  activities  represent the net income earned by Aon in
the reported  periods adjusted for non-cash charges as well as changes in assets
and liabilities. Cash flows provided by operating activities for the first three
months 2002 were $191 million,  a $141 million  decrease over the same period in
2001. Other receivables and liabilities  decreased $109 million during the year,
driven by  incentive  compensation  payments  of $42  million  and a tax related
refund  receivable of $48 million.  The  year-over-year  difference in valuation
changes on  investments,  income on disposals and impairments  represents  lower
valuations  on  the  company's  LP  portfolio  and  higher  impairment  loss  on
investments  that occurred in 2001.  These items were somewhat  offset by higher
net income and the timing of income tax payments and refunds.

Investing activities used cash of $5 million,  versus cash usage of $186 million
in 2001.  The net purchase of  investments  used cash of $251 million during the
first  three  months  of 2002.  This was  offset  by the net sale of  short-term
investments of $337 million. In 2001,  purchases of short-term  investments used
$180 million, while net sales of investments generated cash of $99 million.

Cash of $55 million was used during the first three months of 2002 for financing
activities,  which was $321 million  less than was  utilized in 2001.  The lower
usage of cash from  last year is  primarily  due to a  smaller  decrease  in the
amount of short-term debt paid down, coupled with a larger increase in long-term
debt issued. In 2001, a significant amount of U.S.  commercial paper was repaid,
in part due to utilizing  cash  from  a dividend  received   from  one  of Aon's
insurance  company subsidiaries.

Aon's operating subsidiaries anticipate that there will be adequate liquidity to
meet their needs in the foreseeable future.  Aon's liquidity needs are primarily
for  servicing  its debt and for the payment of  dividends  on stock  issues and
capital securities.  Brokerage  cash flow has been used  primarily for  business
reinvestment,  acquisition financing and payments of special charge and purchase
accounting liabilities.  Aon anticipates  continuation of the company's positive
cash flow and the  ability  of the parent  company to access adequate short-term
lines of credit.

Upon the  completion  of the spin-off of Combined  Specialty,  the "new" Aon and
Combined  Specialty  Boards of Directors will each determine their own post-spin
dividend policy based on consideration of earnings, cash flow, capital needed to
support growth,  regulatory requirements and other factors. Aon's management has
recommended  that the quarterly  cash dividend for "new" Aon be $0.15 per share.
Combined Specialty plans to reinvest a significant  portion of its cash flows in
order to accelerate  earnings  growth and improve  total returns on capital.  As
such, the proposed quarterly dividend rate for Combined Specialty is expected to
be $0.11 per share, based upon  the  post-distribution  share  allocation.

Aon intends to distribute in the spin-off one share of Combined Specialty common
stock for every three shares of Aon common  stock.  Accordingly,  it is expected
that Aon  stockholders  who continue to hold their shares of Combined  Specialty
stock will initially receive total quarterly cash dividends with respect to each
of their shares of Aon stock,  taken together with the dividends on the Combined
Specialty stock  distributed in respect of that share, of approximately  $0.186,
compared with Aon's most recent quarterly dividend of $0.225 per share.

                                     - 20 -


Due to the contractual nature of its insurance policyholder  liabilities,  which
are primarily intermediate to long-term in nature, Aon has invested primarily in
fixed  maturities.  With a carrying  value of $2.4  billion,  Aon's  total fixed
maturity  portfolio is invested primarily in investment grade holdings (95%) and
has a fair value that is 98% of amortized cost at March 31, 2002.

Total  assets  increased  $724 million to $23.1  billion  since  year-end  2001.
Invested  assets at March 31, 2002 decreased  $151 million from year-end  levels
due in part to lower guaranteed  investment contracts and unrealized losses. The
amortized  cost and fair  value of less than  investment  grade  fixed  maturity
investments at March 31, 2002 were $123 million and $115 million,  respectively.
The carrying value of non-income  producing  investments  in Aon's  portfolio at
March 31, 2002 was $25 million, or 0.4% of total invested assets.

Short-term  borrowings decreased at the end of first quarter 2002 by $45 million
when compared to year-end 2001 due to lower international borrowings. At the end
of first quarter 2002,  notes payable  increased by $96 million when compared to
year-end 2001. The increase was due to higher U.S.  commercial  paper borrowings
of $183  million  partially  offset  by the  repayment  of  foreign  debt of $86
million.  Commercial  paper borrowings have been included in notes payable based
on Aon's  intent and ability to maintain or  refinance  these  obligations  on a
long-term basis through 2005.

Stockholders' equity increased $8 million during the first three months of 2002,
reflecting an increase in net income before preferred dividends of $104 million.
Partially  offsetting the increase were dividends  paid to  stockholders  of $62
million.  Unrealized  investment gains and losses and foreign exchange gains and
losses   fluctuations  from  period  to  period  are  largely  based  on  market
conditions.

At March 31, 2002,  stockholders'  equity per share was $12.97, down from $13.03
at December 31, 2001 as the slightly  higher equity balance was more than offset
by the increased number of shares outstanding since year-end.


REVIEW BY INDEPENDENT AUDITORS
- ------------------------------

The condensed  consolidated  financial statements at March 31, 2002, and for the
three months then ended have been  reviewed,  prior to filing,  by Ernst & Young
LLP, Aon's independent auditors, and their report is included herein.

                                     - 21 -

INDEPENDENT ACCOUNTANTS' REVIEW REPORT



Board of Directors and Stockholders
Aon Corporation

We have reviewed the accompanying  condensed consolidated statement of financial
position of Aon  Corporation  as of March 31,  2002,  and the related  condensed
consolidated  statements  of income and cash flows for the  three-month  periods
ended March 31, 2002 and 2001. These financial statements are the responsibility
of the Company's management.

We  conducted  our  reviews in  accordance  with  standards  established  by the
American  Institute  of  Certified  Public  Accountants.  A  review  of  interim
financial  information consists principally of applying analytical procedures to
financial  data, and making  inquiries of persons  responsible for financial and
accounting matters. It is substantially less in scope than an audit conducted in
accordance  with auditing  standards  generally  accepted in the United  States,
which will be performed  for the full year with the  objective of  expressing an
opinion regarding the financial statements taken as a whole. Accordingly,  we do
not express such an opinion.

Based on our reviews, we are not aware of any material modifications that should
be made to the accompanying condensed consolidated financial statements referred
to above  for them to be in  conformity  with  accounting  principles  generally
accepted in the United States.

We have  previously  audited,  in accordance with auditing  standards  generally
accepted in the United States, the consolidated  statement of financial position
of Aon  Corporation  as of  December  31,  2001,  and the  related  consolidated
statements  of income,  stockholders'  equity,  and cash flows for the year then
ended,  not  presented  herein,  and in our report dated  February 12, 2002,  we
expressed an unqualified opinion on those consolidated financial statements.  In
our  opinion,   the  information  set  forth  in  the   accompanying   condensed
consolidated  statement of financial position as of December 31, 2001, is fairly
stated, in all material respects,  in relation to the consolidated  statement of
financial position from which it has been derived.




                                                               ERNST & YOUNG LLP

Chicago, Illinois
April 29, 2002

                                     - 22 -


                                     PART II
                                     -------

                                OTHER INFORMATION
                                -----------------


ITEM 4.                  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

      (a)   The Annual  Meeting of  Stockholders  of the  Registrant was held on
            April 19, 2002 (the "2002 Annual Meeting").

      (b)   Not applicable.

      (c)(i)   Name                           For                  Against
               ----                           ---                  -------

               Edgar D. Jannotta          242,634,156             3,176,884
               Lester B. Knight           243,758,835             2,052,205
               Perry J. Lewis             242,694,240             3,116,800
               R. Eden Martin             242,690,666             3,120,374
               Andrew J. McKenna          242,659,963             3,151,077
               Robert S. Morrison         243,751,788             2,059,252
               Richard C. Notebaert       243,734,656             2,076,384
               Michael D. O'Halleran      243,352,771             2,458,269
               John W. Rogers, Jr.        242,700,482             3,110,558
               Patrick G. Ryan            243,756,180             2,054,860
               Patrick G. Ryan, Jr.       241,426,894             4,384,146
               George A. Schaefer         242,669,800             3,141,240
               Raymond I. Skilling        243,715,937             2,095,103
               Carolyn Y. Woo             242,691,926             3,119,114


            (ii)  Set forth below is the tabulation of the vote on the selection
                  of Ernst & Young LLP as auditors  for the  Registrant  for the
                  2002 fiscal year.

                         For                Against                  Abstain
                         ---                -------                  -------

                     239,220,162           5,578,198                1,012,680

      (d)   Not applicable.



ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K

      (a)   Exhibits - The  exhibits  filed  with this  report are listed on the
            --------
            attached Exhibit Index.

      (b)   Reports on Form 8-K - No Current  Reports on Form 8-K were filed for
            -------------------
            the quarter ended March 31, 2002.

                                     - 23 -


SIGNATURE

Pursuant to the  requirements  of the  Securities  and Exchange Act of 1934, the
Registrant  has duly  caused  this  report  to be  signed  on its  behalf by the
undersigned thereunto duly authorized.


                                    Aon Corporation
                                    (Registrant)

May 2, 2002                         /s/ Harvey N. Medvin
                                    --------------------
                                    HARVEY N. MEDVIN
                                    EXECUTIVE VICE PRESIDENT AND
                                    CHIEF FINANCIAL OFFICER
                                    (Principal Financial and Accounting Officer)

                                     - 24 -


Aon CORPORATION
- ---------------

Exhibit Number
In Regulation S-K


Item 601 Exhibit Table
- ----------------------



(12)  Statements regarding Computation of Ratios.

      (a)   Statement  regarding  Computation  of  Ratio  of  Earnings  to Fixed
            Charges.

      (b)   Statement  regarding  Computation  of Ratio of  Earnings to Combined
            Fixed Charges and Preferred Stock Dividends.


(15)  Letter re: Unaudited Interim Financial Information



                                     - 25 -





                                                                                                                      EXHIBIT 12(A)

                                             AON CORPORATION AND CONSOLIDATED SUBSIDIARIES
                                               COMBINED WITH UNCONSOLIDATED SUBSIDIARIES
                                           COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES


                                                        THREE MONTHS ENDED
                                                            MARCH 31,                          YEARS ENDED DECEMBER 31,
                                                       --------------------  ------------------------------------------------------
 (millions except ratios)                                2002       2001       2001        2000       1999       1998       1997
                                                       ---------  ---------  ---------  ---------- ---------- ---------- ----------
                                                                                                        
 Income before provision for income taxes
     and minority interest (1)                            $ 181       $ 48      $ 399       $ 854      $ 635      $ 931      $ 542

 ADD BACK FIXED CHARGES:

     Interest on indebtedness                                29         36        127         140        105         87         70

     Interest on ESOP                                         -          -          -           -          1          2          3

     Portion of rents representative of interest factor      15         14         57          54         49         51         44

                                                       ---------  ---------  ---------  ---------- ---------- ---------- ----------
       INCOME AS ADJUSTED                                 $ 225       $ 98      $ 583      $1,048      $ 790     $1,071      $ 659
                                                       =========  =========  =========  ========== ========== ========== ==========


 FIXED CHARGES:

     Interest on indebtedness                              $ 29       $ 36      $ 127       $ 140      $ 105       $ 87       $ 70

     Interest on ESOP                                         -          -          -           -          1          2          3


     Portion of rents representative of interest factor      15         14         57          54         49         51         44

                                                       ---------  ---------  ---------  ---------- ---------- ---------- ----------
       TOTAL FIXED CHARGES                                 $ 44       $ 50      $ 184       $ 194      $ 155      $ 140      $ 117
                                                       =========  =========  =========  ========== ========== ========== ==========

 RATIO OF EARNINGS TO FIXED CHARGES                         5.1        2.0        3.2         5.4        5.1        7.6        5.6
                                                       =========  =========  =========  ========== ========== ========== ==========
<FN>
(1)  Income before provision from income taxes and minority interest includes an
     unusual charge of $90 million established as an allowance for a potentially
     uncollectible  receivable  related to a dispute with reinsurers over claims
     related  to the  World  Trade  Center,  as well as a  special  charge of $5
     million  pertaining to the spin-off of Combined  Specialty Group, Inc., for
     the  three  months  ended  March 31, 2002, and  $72 million  related to the
     business transformation  plan  for  the three months ended  March 31, 2001,
     respectively.

     Income  before  provision for income taxes and minority  interest  includes
     unusual  charges of $68 million  related to the World Trade Center  attacks
     for the year ended  December 31, 2001 and special  charges of $218 million,
     $82 million,  $313 million,  and $172 million for the years ended  December
     31, 2001, 2000, 1999, and 1997, respectively.
</FN>





                                                                                                                       EXHIBIT 12(B)

                                                   AON CORPORATION AND CONSOLIDATED SUBSIDIARIES
                                                     COMBINED WITH UNCONSOLIDATED SUBSIDIARIES
                                            COMPUTATION OF RATIO OF EARNINGS TO COMBINED FIXED CHARGES
                                                            AND PREFERRED STOCK DIVIDENDS


                                                       THREE MONTHS ENDED
                                                             MARCH 31,                    YEARS ENDED DECEMBER 31,
                                                      --------------------- -------------------------------------------------------
(millions except ratios)                                2002        2001      2001        2000        1999       1998       1997
                                                      ---------  ---------- ----------  ---------  ----------  ---------  ---------
                                                                                                        
Income before provision for income taxes
    and minority interest (1)                            $ 181        $ 48      $ 399      $ 854       $ 635      $ 931      $ 542

ADD BACK FIXED CHARGES:

    Interest on indebtedness                                29          36        127        140         105         87         70

    Interest on ESOP                                         -           -          -          -           1          2          3

    Portion of rents representative of interest factor      15          14         57         54          49         51         44

                                                      ---------  ---------- ----------  ---------  ----------  ---------  ---------
      INCOME AS ADJUSTED                                 $ 225        $ 98      $ 583     $1,048       $ 790     $1,071      $ 659
                                                      =========  ========== ==========  =========  ==========  =========  =========


FIXED CHARGES AND PREFERRED STOCK DIVIDENDS:

    Interest on indebtedness                              $ 29        $ 36      $ 127      $ 140       $ 105       $ 87       $ 70

    Preferred stock dividends                               17          17         70         70          70         70         82

                                                      ---------  ---------- ----------  ---------  ----------  ---------  ---------
        INTEREST AND DIVIDENDS                              46          53        197        210         175        157        152

    Interest on ESOP                                         -           -          -          -           1          2          3

    Portion of rents representative of interest factor      15          14         57         54          49         51         44

                                                      ---------  ---------- ----------  ---------  ----------  ---------  ---------
        TOTAL FIXED CHARGES AND PREFERRED
        STOCK DIVIDENDS                                   $ 61        $ 67      $ 254      $ 264       $ 225      $ 210      $ 199
                                                      =========  ========== ==========  =========  ==========  =========  =========

RATIO OF EARNINGS TO COMBINED FIXED
    CHARGES AND PREFERRED STOCK DIVIDENDS (2)              3.7         1.5        2.3        4.0         3.5        5.1        3.3
                                                      =========  ========== ==========  =========  ==========  =========  =========
<FN>

(1)  Income before provision from income taxes and minority interest includes an
     unusual charge of $90 million established as an allowance for a potentially
     uncollectible  receivable  related to a dispute with reinsurers over claims
     related  to the  World  Trade  Center,  as well as a  special  charge of $5
     million  pertaining  to the spin-off of Combined Specialty Group, Inc., for
     the three  months  ended March 31, 2002, and  $72  million  related  to the
     business transformation  plan  for the three months  ended  March 31, 2001,
     respectively.

     Income  before  provision for income taxes and minority  interest  includes
     unusual  charges of $68 million  related to the World Trade Center  attacks
     for the year ended  December 31, 2001 and special  charges of $218 million,
     $82 million,  $313 million,  and $172 million for the years ended  December
     31, 2001, 2000, 1999, and 1997, respectively.

(2)  Included  in total fixed  charges and  preferred  stock  dividends  are $16
     million for the three months ended March 31, 2002 and 2001, $66 million for
     the years ended December 31, 2001, 2000, 1999 and 1998, and $64 million for
     the year ended  December 31, 1997,  of pretax  distributions  on the 8.205%
     mandatorily redeemable preferred capital securities which are classified as
     "minority interest" on the condensed consolidated statements of income.

</FN>



                                                                      Exhibit 15




Board of Directors and Stockholders
Aon Corporation


We are aware of the incorporation by reference in the Registration Statements of
Aon  Corporation  ("Aon")  described in the following  table of our report dated
April  29,  2002  relating  to  the  unaudited  condensed  consolidated  interim
financial  statements of Aon Corporation  that are included in its Form 10-Q for
the quarter ended March 31, 2002:

        Registration Statement
        ----------------------
         Form          Number                     Purpose
         ----          ------                     -------

         S-8          33-27984          Pertaining to Aon's savings plan
         S-8          33-42575          Pertaining to Aon's stock award plan and
                                          stock option plan
         S-8          33-59037          Pertaining to Aon's stock award plan and
                                          stock option plan
         S-4          333-21237         Offer to exchange Capital Securities of
                                          Aon Capital A
         S-3          333-50607         Pertaining to the registration of
                                          369,000 shares of common stock
         S-8          333-55773         Pertaining  to Aon's  stock  award plan,
                                          stock option plan and employee stock
                                          purchase plan
         S-3          333-78723         Pertaining to the registration of debt
                                          securities, preferred stock and common
                                          stock
         S-3          333-49300         Pertaining to the registration of
                                          3,864,824 shares of common stock
         S-4          333-57706         Pertaining to the  registration  of a
                                          proposed  issuance of up to 3,852,184
                                          shares of common stock to the
                                          stockholders of ASI Solutions, Inc.
         S-3          333-65624         Pertaining to the registration of
                                          2,000,000 shares of common stock
         S-3          333-74364         Pertaining to the registration of debt
                                          securities, preferred stock, common
                                          stock, share purchase contracts, and
                                          share purchase units


Pursuant to Rule 436(c) of the  Securities Act of 1933, our report is not a part
of the registration  statements  prepared or certified by accountants within the
meaning of Section 7 or 11 of the Securities Act of 1933.


                                                               ERNST & YOUNG LLP



Chicago, Illinois
April 29, 2002