Science fiction anthologists will run out of anthology ideas the day Madison Avenue runs out of ways to sell deodorants. This one results in a better collection than anybody has a right to expect. There is a certain amount of harmless cutesiness (an unwilling Santa, complete with eight indignant alien ""reindeer,"" negotiating a chimney touchdown in Asimov's ""Christmas on Ganymede""), but Carr keeps surprisingly clear of the more saccharine possibilities. Among the best things here are Gordon R. Dickson's quiet story of unsung Christmas self-sacrifice, James White's witty, suspenseful ""Christmas Treason"" (a handful of telekinetic moppets with a deep interest in the entire North Pole arsenals of the US and the USSR), and Brian Aldiss' cheerful updating of the Father Christmas legend for the Age of Expendable Humanity. Characteristically, an early Frederik Pohl combines some gorgeous satire of Yuletide commercialism with a pretty' wimpy view of the alternatives. Other contributors: Frank M. Robinson, John Christopher, Arthur C. Clarke (the excellent ""The Star"").