1. Name and Address of Reporting Person * Blue Harbour Group, LP	2. Date of Event Requiring Statement (MM/DD/YYYY) 12/2/2013	3. Issuer Name and Ticker or Trading Symbol CACI INTERNATIONAL INC /DE/ [CACI]
(Last)        (First)        (Middle) 646 STEAMBOAT ROAD	4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                            ___ X ___ 10% Owner _____ Officer (give title below)          _____ Other (specify below)
(Street) GREENWICH, CT 06830        (City)              (State)              (Zip)	5. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) ___ Form filed by One Reporting Person _ X _ Form filed by More than One Reporting Person

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	2362205	I	See footnote   (1) (2)

Table II - Derivative Securities Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 4)	2. Date Exercisable and Expiration Date (MM/DD/YYYY)		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

Explanation of Responses:
(1)	This Form 3 is filed by Blue Harbour Group, LP (the "Manager"), Blue Harbour Holdings, LLC ("Manager GP") and Clifton S. Robbins. Manager GP is the general partner of Manager. Mr. Robbins directly and indirectly through trusts or other entities controlled by Mr. Robbins is the controlling shareholder of Manager GP.
(2)	Pursuant to Rule 16a-1 under the Securities Exchange Act of 1934, as amended (the "Act"), each of the Reporting Persons may be deemed to be the beneficial owner of the securities reported herein to the extent of his or its pecuniary interest therein, but disclaims beneficial ownership in excess of such amount; and pursuant to Rule 16a-1(a)(4) under the Act, this filing shall not be deemed an admission that any of the Reporting Persons is, for purposes of Section 16 of the Act or otherwise, the beneficial owner of any securities reported herein in excess of such amount.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Blue Harbour Group, LP 646 STEAMBOAT ROAD GREENWICH, CT 06830		X
Blue Harbour Holdings, LLC 646 STEAMBOAT ROAD GREENWICH, CT 06830		X
ROBBINS CLIFTON S 626 STEAMBOAT ROAD GREENWICH, CT 06830		X

Signatures
/s/ Clifton S. Robbins, Managing Member of Blue Harbour Holdings, LLC, the General Partner of Blue Harbour Group, LP		12/5/2013
** Signature of Reporting Person		Date
/s/ Clifton S. Robbins, Managing Member of Blue Harbour Holdings, LLC		12/5/2013
** Signature of Reporting Person		Date
/s/ Clifton S. Robbins		12/5/2013
** Signature of Reporting Person		Date

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
*	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).
Note:	File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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.