Harry Max Harrison (born Henry Maxwell Dempsey; March 12, 1925 – August 15, 2012) was an American science fiction (SF) author, best known for his character the Stainless Steel Rat and for his novel Make Room! Make Room! (1966). The latter was the rough basis for the motion picture Soylent Green (1973). Harrison was (with Brian Aldiss) the co-president of the Birmingham Science Fiction Group.