this essay explores the emergence of the mexican supreme court and the colombian constitutional court as powerful political actors. mexico and colombia undertook constitutional transformations designed to empower their respective national high courts in the 1990s to facilitate a democratic transition. these constitutional transformations opened up political space for the mexican supreme court and the colombian constitutional court to begin to displace political actors in the tasks of constitutional construction and maintenance. these two courts play different roles, however, in their respective democratic orders. mexico chose to empower its supreme court to police vertical and horizontal separation of powers whereas colombia fashioned a constitutional court whose task is to deepen the social bases of democracy by constructing rights. this essay argues that the constitutional changes that occurred are a necessary but not sufficient explanation for the role these two courts play. the agenda courts undertake is shaped both by short-term political bargains and by long-term societal transformations. as a result of both the bargains that led to the adoption of a new constitution and broader intellectual transformations regarding the role of courts in effectuating constitutional guarantees, the colombian constitutional court has pursued a more ambitious agenda than the mexican supreme court.