  Compositional Game Theory is a new, recently introduced model of economic
games based upon the computer science idea of compositionality. In it, complex
and irregular games can be built up from smaller and simpler games, and the
equilibria of these complex games can be defined recursively from the
equilibria of their simpler subgames. This paper extends the model by providing
a final coalgebra semantics for infinite games. In the course of this, we
introduce a new operator on games to model the economic concept of subgame
perfection.
