For immediate release: June 21, 2006

Withdrawal Of Engineering Services at Brampton Operations

Richmond, B.C. - MacDonald, Dettwiler and Associates Ltd., a provider of essential information solutions, announced today that the engineers association (SPATEA) of its Brampton, Ontario operations has withdrawn its services. The current collective agreement expired on December 31, 2005. The Company will continue its effort to reach a new collective agreement.