The principal aim of this book is to reconcile game and decision theory within the subjectivist framework of rational choice. Traditional game theory, grounded in objectivist decision theory, shows clear limitations in explaining human behavior. By contrast, subjectivist decision theory appears far better suited to describe and anticipate decision making in real-life situations of rational choice and strategic conflict. The author extends Savage's groundbreaking approach to rational choice through a rigorous application of counterfactual reasoning. This principle is likewise employed to address strategic conflicts in a concise manner, departing from the ubiquitous equilibrium doctrine. To this end, he distinguishes between static, dynamic, and coherent games. The latter is new to game theory and describes situations in which all players know what the others are going to do. This gives rise to strategic interaction—an aspect largely overlooked in traditional game theory. The presented insights differ essentially from those obtained in traditional game theory. To facilitate a better understanding of the theoretical developments, alternative concepts of game theory are also examined. These comprise not only the objectivist approach, but also the epistemic approach and the theory of moves. The author concludes with a discussion of profound philosophical questions concerning determinism, freedom of choice, and causality, all of which are closely related to the subject matter. The book thus offers a fresh and modern perspective on game and decision theory.