EXHIBIT A

JOINT FILING AGREEMENT

The undersigned agree that this Sixth Amendment dated June 16, 2009, relating to Argyle Security, Inc., shall be filed on behalf of the undersigned.

MEZZANINE MANAGEMENT FUND IV A, L.P.
By:	/s/ Christopher C. Morris
	Name:	Christopher C. Morris
	Title:	Authorized Signatory
MEZZANINE MANAGEMENT FUND IV COINVEST A, L.P.
By:	/s/ Christopher C. Morris
	Name:	Christopher C. Morris
	Title:	Authorized Signatory
MEZZANINE MANAGEMENT LIMITED
By:	/s/ Christopher C. Morris
	Name:	Christopher C. Morris
	Title:	Authorized Signatory