Note: Tuck states that the book appeared in 1951, but all other sources agree on 1952. Only Heinlein is credited on the title page. The list of actual editors reconstructed from the introduction. According to Bill Patterson, who reviewed the correspondence between the editors at one point (http://groups.google.com/group/rec.arts.sf.written/msg/6ec509cd5e4fcd57): "Both Truman (Mac") Talley and Walter Bradbury did participate in the editorial process, but not to the same extent as Heinlein and Merril. They both read and commented on the first and second round of manuscript selections, for example. If I had to put it in descending order of amount of work it would be (1) Merril for doing all the legwork of gathering the nominated stories and sending them around and getting the permissions on the finished work; (2) Heinlein for general oversight of the selection process plus the introduction; (3) Bradbury for more comments on contents than Talley but (4) Talley did make some comments on selection. (5) Pohl comes last simply because I don't recall any direct input from him, but he may deserve to be higher on the list -- after Heinlein, say, but before Bradbury -- simply because his participation might well be hidden in Merril's.