a Headquarters and four subordinate task groups--a Scientific Task Group, an Army Task Group, a Navy Task Group, and an Air Force Task Group. The Executive Agent for the Task Force had been the Chief of Staff, U. S. Army (C/S, USA), and Major General P. W. Clarkson, United States Army, had served as the Commander. IVY, itself, witnessed two large yield detonations-—-the MIKE device and the KING weapon in that order—~and by the time of the KING detonation in mid-November, the broad planning for a subsequent overseas test, to be known as Operation CASTLE, wasalready seven months advanced. As early as mid~April, 1952, informal know- ledge had been received in the Task Force Washington Headquarters indicating that the next overseas test would occur about ten months after the campleticn of Operation IVY, i. e., on or about 1 Septenber, 1953. This development immediately altered the complexion of IVY roll-up planning and stimulated thought with regard to efficient and economical continuity in Department of Defense (DOD) participa- tion in overseas tests. Because of the impact on IVY of the proximity of the CASTLE date, CJTF 132 had sent a letter on the matter to the Executive Agent on 12 May. This letter was followed within a few days with a Pent- agon briefing of Service and Armed Forces Special Weapons Project (AFSWP ) representatives by General Clarkson and his staff operations officer. This letter and the briefing outlined the major factors which would influence the nature of IVY roll-up and noted the im- no plications for CASTLE planning carried by these same factors. At