Paul Samuelson's Foundations of Economic Analysis played a major role in defining how economic theory was undertaken for many years after the Second World War. This paper fills out Samuelson's account of the book's origins and corrects some details, making clear his debt to E. B. Wilson and establishes that turning the thesis into a book was a long process. The contents of the book and its reception are then reviewed. ( JEL A22, B20, B31)