FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL OMB Number: 3235-0104 Expires: January 31, 2005 Estimated average burden hours per response... 0.5

(Print or Type Responses)

1. Name and Address of Reporting Person *   Ledford Laurie 2. Date of Event Requiring Statement (Month/Day/Year) 04/02/2012 3. Issuer Name and Ticker or Trading Symbol MARSH & MCLENNAN COMPANIES, INC. [MMC] (Last) (First) (Middle) C/O MARSH & MCLENNAN COMPANIES, INC., 1166 AVENUE OF THE AMERICAS 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) SVP & Chief HR Officer 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) NEW YORK, NY 10036 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Stock 2,981.5441 D   Common Stock (SIP) 561.159 D Â

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
	Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stk. Units (SSIP)	  (1)	  (1)	Common Stock	946.972	$ (2)	D	Â
Restricted Stock Units	  (1)	  (1)	Common Stock	10,177	$ (2)	D	Â
Stock Options (Right to Buy)	  (3)	03/16/2014	Common Stock	2,315	$ 27.86	D	Â
Stock Options (Right to Buy)	  (4)	03/15/2015	Common Stock	5,000	$ 30.505	D	Â
Stock Options (Right to Buy)	  (5)	02/11/2017	Common Stock	3,601	$ 29.6	D	Â
Stock Options (Right to Buy)	  (6)	02/21/2020	Common Stock	30,928	$ 22.705	D	Â
Stock Options (Right to Buy)	  (7)	02/20/2021	Common Stock	11,245	$ 30.595	D	Â
Stock Options (Right to Buy)	  (8)	02/23/2022	Common Stock	12,418	$ 31.885	D	Â
Stock Options (Right to Buy)	07/01/2007	03/19/2013	Common Stock	3,000	$ 27.86	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Ledford Laurie C/O MARSH & MCLENNAN COMPANIES, INC. 1166 AVENUE OF THE AMERICAS NEW YORK, NY 10036	Â	Â	  SVP & Chief HR Officer	Â

Signatures

Katherine J. Brennan		04/12/2012
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Not Applicable.
(2)	The security converts to Marsh & McLennan Companies common stock on a 1-for-1 basis.
(3)	These options were granted on July 1, 2005. 1,736 of these options vested and became exercisable on July 1, 2007. The remaining 579 of these options vested and became exercisable on March 17, 2008.
(4)	These options vested in four equal annual installments on March 16th of 2006, 2007, 2008, and 2009. These options become exercisable only if, after they are vested, the closing price of Marsh & McLennan Companies common stock is at least 15% higher than the exercise price of the options for ten consecutive trading days.
(5)	These options vested in four equal annual installments on February 12th of 2008, 2009, 2010, and 2011. These options become exercisable only if, after they are vested, the closing price of Marsh & McLennan Companies common stock is at least 15% higher than the exercise price of the options for ten consecutive trading days.
(6)	These options were granted on February 22, 2010 and vest in four equal annual installments beginning on the first anniversary of the grant date. The first two installments vested and became exercisable on February 22, 2011 and February 22, 2012. The remaining installments vest on February 22, 2013 and February 22, 2014.
(7)	These options were granted on February 21, 2011 and vest in four equal annual installments beginning on the first anniversary of the grant date. The first installment vested and became exercisable on February 21, 2012. The remaining installments vest on February 21, 2013, February 21, 2014, and February 21, 2015.
(8)	These options vest in four equal annual installments on February 24, 2013, February 24, 2014, February 24, 2015, and February 24, 2016.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.