The Brest Maritime Works Directorate (direction des travaux maritimes de Brest, now Direction régionale du service d'infrastructure de la Défense de Brest) was the name of one of the decentralised directorates within France's SID (Service d'infrastructure de la défense). It is based at Brest and it oversees the expansion and maintenance of the French Navy's military infrastructure in Brest's military port and its annexes, in the operational base on Île Longue, the Lorient military port and the signal-stations chain along the west Brittany coast.