Abstract. Given a set of strings S = {s1, . . . , sn}, the Shortest Superstring problem asks for the shortest string s which contains each si as a substring. We consider two measures of success in this problem: the length measure, which is the length of s, and the compression measure, which is the difference between the sum of lengths of the si and the length of s. Both the length and the compression versions of the problem are known to be MAX-SNP-hard. The only explicit approximation ratio