This article addresses the question of how terrorism declines and the role that different stakeholders within different contexts contribute to this phenomenon, particularly governments. It first addresses the point that disengagement from terrorism is an under researched area and starts with the assumption that government policies of prevention and deterrence are the key determinants of outcomes. It then identifies the attitude of public public-policy makers towards historical research and the inadequacy of data as barriers to terrorism research and concludes that the decline of terrorism can be attributed to three factors: physical defeat of the extremist organisation by the government, the group’s decision to abandon the terrorist strategy and organisational disintegration. (The decline of oppositional terrorism is a critical question for both scholars and policy‐makers. The former have neglected the issue, while the latter have tended to assume that government policies of prevention and deterrence are the key determinants of outcomes. This analysis suggests that government actions must be seen in the context of the internal organizational dynamics and strategy of the opposition groups using terrorism. In some cases, terrorism is self‐defeating.