EXHIBIT A

JOINT FILING AGREEMENT

The undersigned agree that this Amendment dated January 14, 2009 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: Name:		/s/ Dudley R. Cottingham Dudley R. Cottingham
		Title:		Authorized Signatory
		MEZZANINE MANAGEMENT FUND IV COINVEST A
		By: Name:		/s/ Dudley R. Cottingham Dudley R. Cottingham
		Title:		Authorized Signatory
		MEZZANINE MANAGEMENT LIMITED
		By: Name:		/s/ Dudley R. Cottingham Dudley R. Cottingham
		Title:		Authorized Signatory