Registration No. 333-144127
Filed Pursuant to Rule 424(b)(3)

PROSPECTUS SUPPLEMENT NO. 4

(TO PROSPECTUS DATED OCTOBER 11, 2007)

$300,000,000

CACI International Inc

2.125% Convertible Senior Subordinated Notes due 2014

and Shares of Common Stock Issuable upon Conversion of the Notes

This prospectus supplement relates to the resale by the holders of 2.125% Convertible Senior Subordinated Notes due 2014 of CACI International Inc and the shares of common stock issuable upon conversion of the notes.

This prospectus supplement should be read in conjunction with the prospectus dated October 11, 2007, as previously supplemented, which is to be delivered with this prospectus supplement. This prospectus supplement is not complete without, and may not be delivered or used except in conjunction with, the prospectus, including any amendments or supplements thereto.

Investing in the notes or our common stock involves a high degree of risk. You should carefully read and consider the “Risk Factors” beginning on page 6 of the prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement or the prospectus. Any representation to the contrary is a criminal offense.

The date of this prospectus supplement is November 19, 2007

The information in the table appearing under the heading “Selling Securityholders” in the prospectus, as previously supplemented, is supplemented and superseded in part by the information appearing in the table below. Because selling securityholders may trade all or some of the notes listed at any time without notifying us, the table may not reflect the exact value of notes held by each selling securityholder on the date of this supplement.

	Principal Amount of Notes Beneficially Owned that may be Offered ($)	Percentage of Notes Outstanding		Number of Shares of Common Stock Beneficially Owned (1)	Number of Shares of Common Stock that may be Offered (1)	Percentage of Common Stock Outstanding (2)	Number of Shares of Common Stock upon Completion of the Offering (3)
CIBC World Markets Corp (4)	1,500,000	*		27,448	27,448	*	0
JP Morgan Securities Inc. (5)	7,050,000	2.35	%	129,007	129,007	*	0
Radcliffe SPC, Ltd. for and on behalf of the Class A Segregated Portfolio (6)	9,500,000	3.17	%	173,839	173,839	*	0

* Less than 1%.

(1) Assumes conversion of all of the holder’s notes at a conversion rate of 18.2989 shares of common stock per $1,000 principal amount of notes. However, this conversion rate is subject to adjustment as described under “Description of notes — Conversion rights.” As a result, the number of shares of common stock issuable upon conversion of the notes may increase or decrease in the future.

(2) Calculated based on Rule 13d-3(d)(1), using 30,003,706 shares of common stock outstanding as of October 1, 2007. In calculating this amount for each holder, the number of shares of common stock issuable upon conversion of all of that holder’s notes, but not any other holder’s notes, are treated as outstanding.

(3) The information presented assumes that all of the selling securityholders will fully convert the notes for shares of our common stock and that the selling securityholders will sell all shares of our common stock that they received pursuant to such conversion.

(4) Chris Molloy is the Executive Director of CIBC World Markets Corp and is the natural person having dispositive power over the securities being offered. CIBC World Markets Corp has identified itself as a registered broker-dealer and, accordingly, it is, under the interpretations of the Securities and Exchange Commission, an “underwriter” within the meaning of the Securities Act of 1933.

(5) JP Morgan Securities, Inc. is a reporting company under the Exchange Act. JP Morgan Securities, Inc. has identified itself as a registered broker-dealer and, accordingly, it is, under the interpretations of the Securities and Exchange Commission, an “underwriter” within the meaning of the Securities Act of 1933.

(6) Pursuant to an investment management agreement, RG Capital Management, L.P. (“RG Capital”) serves as the investment manager of Radcliffe SPC, Ltd.’s Class A Segregated Portfolio. RGC Management Company, LLC (“Management”) is the general partner of RG Capital. Steve Katznelson and Gerald Stahlecker serve as the managing members of Management. Each of RG Capital, Management and Messsr. Katznelson and Stahlecker disclaims beneficial ownership of the securities owned by Radcliffe SPC, Ltd. for and on behalf of the Class A Segregated Portfolio.

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