<ARTICLE>                     5
<LEGEND>
This  schedule  contains  summary  financial   information  extracted  from  the
consolidated  Marsh & McLennan  Companies,  Inc. and subsidiaries  September 30,
1999 financial  statements and is qualified in its entirety by reference to such
financial statements.
</LEGEND>

                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                              DEC-31-1999
<PERIOD-END>                                   SEP-30-1999
<CASH>                                         641,000,000
<SECURITIES>                                             0
<RECEIVABLES>                                2,238,000,000
<ALLOWANCES>                                    85,000,000
<INVENTORY>                                              0
<CURRENT-ASSETS>                             3,403,000,000
<PP&E>                                       2,160,000,000
<DEPRECIATION>                                 814,000,000
<TOTAL-ASSETS>                              12,389,000,000
<CURRENT-LIABILITIES>                        3,559,000,000
<BONDS>                                      2,591,000,000
<PREFERRED-MANDATORY>                                    0
<PREFERRED>                                              0
<COMMON>                                       268,000,000
<OTHER-SE>                                   4,004,000,000
<TOTAL-LIABILITY-AND-EQUITY>                12,389,000,000
<SALES>                                                  0
<TOTAL-REVENUES>                             6,823,000,000
<CGS>                                                    0
<TOTAL-COSTS>                                5,532,000,000
<OTHER-EXPENSES>                                         0
<LOSS-PROVISION>                                14,000,000
<INTEREST-EXPENSE>                             174,000,000
<INCOME-PRETAX>                              1,134,000,000
<INCOME-TAX>                                   455,000,000
<INCOME-CONTINUING>                            679,000,000
<DISCONTINUED>                                           0
<EXTRAORDINARY>                                          0
<CHANGES>                                                0
<NET-INCOME>                                   679,000,000
<EPS-BASIC>                                         2.60
<EPS-DILUTED>                                         2.47