During 1942 a centralized organization of the OT was created when Speer became Reichsminister. A new HQ in Berlin, Amt OTZ, was created with Ministerialdirigent Franz Xaver Dorsch as chief of staff.[12] It merged during 1944 with Amt Bau-OT to form Amt Bau-OT Zentrale directed by Speer, and with Dorsch as chief, representative of Speer as minister, and as general plenipotentiary for construction.[13]