Although entrepreneurs constitute a key economic driving force for many emerging economies, they often face unstable environments due to the failure of governments to maintain civil and political order. Yet, we know very little about how environments characterized by weak institutions and high levels of political and civil violence directly affect new venture survival. Moreover, it is unclear whether standard theories about organizational strategy, such as planning, hold true in such environments. Building upon the institution-based view of strategy and past research on planning, we explore these issues using a sample of 730 new ventures in Colombia from 1997 to 2001. We find that political and civil violence decreases firm survival, increases the benefits of incremental planning, and decreases the benefits of comprehensive planning.