The theory of adaptationism argues that natural selection contains sufficient explanatory power in itself to account for all evolution. However, there are differing views about the efficiency, or optimality, of the adaptation model of explanation. If the adaptationism theory is applied, are energy and resources being used as optimally as possible? Adaptationism and Optimality combines contributions from biologists and philosophers, and offers a systematic treatment of foundational, conceptual, and methodological issues surrounding the theory of adaptationism.