EXHIBIT A JOINT FILING AGREEMENT

EXHIBIT A

JOINT FILING AGREEMENT

The undersigned agree that this Schedule 13D dated May 5, 2008 relating to the common stock, par value $0.0001, of Argyle Security, Inc. shall be filed on behalf of the undersigned.

	MEZZANINE MANAGEMENT FUND IV A
	By:	/s/ S. Xxxxxx Xxxxxx
	Name:		S. Xxxxxx Xxxxxx
	Title:		Authorized Signatory
	MEZZANINE MANAGEMENT FUND IV COINVEST A
	By:	/s/ S. Xxxxxx Xxxxxx
	Name:		S. Xxxxxx Xxxxxx
	Title:		Authorized Signatory
	MEZZANINE MANAGEMENT LIMITED
	By:	/s/ S. Xxxxxx Xxxxxx
	Name:		S. Xxxxxx Xxxxxx
	Title:		Authorized Signatory

/s/ Xxxx Xxxxxx  

XXXX XXXXXX 

/s/ Xxxxx Xxxx  

XXXXX XXXX