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

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(Print or Type Responses)

1. Name and Address of Reporting Person *   Mead Christopher E 2. Date of Event Requiring Statement (Month/Day/Year) 05/15/2018 3. Issuer Name and Ticker or Trading Symbol GALLAGHER ARTHUR J & CO [AJG] (Last) (First) (Middle) 2850 GOLF ROAD 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) VICE PRESIDENT 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) ROLLING MEADOWS, IL 60008-4002 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 463 D   Common Stock (restricted) (1) 3,750 D Â

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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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
Phantom Stock	  (2)	  (2)	Common Stock	2,813	$ (3)	D	Â
Non-qualified Stock Option	  (4)(5)	05/01/2024	Common Stock	10,000	$ 55.94	D	Â
Non-qualified Stock Option	  (5)(6)	03/15/2025	Common Stock	5,700	$ 70.74	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Mead Christopher E 2850 GOLF ROAD ROLLING MEADOWS, IL 60008-4002	Â	Â	  VICE PRESIDENT	Â

Signatures

/s/ Seth Diehl, by power of attorney		05/24/2018
**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)	Consists of two tranches of restricted stock units: 2,500 granted on 5/1/2017, and 1,250 granted on 3/15/2018, each tranche cliff vesting on the fifth anniversary of the grant date.
(2)	These shares represent awards under the Age 62 Plan, a nonqualified deferred compensation plan of the Company, which have been deemed invested in Company common stock at the election of the reporting person. Participants vest in these awards when they attain age 62, or after a one-year period for participants who have attained age 61.
(3)	Each share of phantom stock represents a right to receive one share of Gallagher common stock.
(4)	Granted on May 1, 2017.
(5)	One-third of this stock option becomes exerciseable on each of the 3rd, 4th, and 5th anniversaries of the grant date.
(6)	Granted on March 15, 2018.

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