 As a background for game semantics, from intuitionistic logic we have the very early Lorenzen (1961) on dialogue games, then from linear logic Lafont and Streicher (1991) and Blass (1992) and from Coquand’s game theoretical analysis of classical provability (Coquand 1995). From combinatorial game theory the categorical account by Joyal (1977), “the first person to make a category of games and winning strategies” according to Abramsky &amp; Jagadeesan (1994). A readable historical account of the first uses of games in the interpretation of constructive logical formalisms, especially linear logic, is included in Abramsky &amp; Jagadeesan 1994. It should be observed that games for logic require winning strategies in order to capture validity, an issue that we have not dealt with at all in this entry.