Dangerous Alliances: Proponents of Peace, Weapons of War. By Patricia A. Weitsman. Stanford: Stanford University Press, 2004. 264p. $49.50.

Patricia Weitsman sets out to provide a unified theory of alliance politics that explains when states will manage threatening neighbors by allying with them rather than allying against them, when allies will undertake different types of military obligations, when alliances will be more or less cohesive, and how alliances aimed at preserving peace sometimes provoke war. Although she is not entirely successful in fulfilling this extensive agenda, Dangerous Alliances is nevertheless a constructive contribution to several ongoing debates about alliance politics.