This paper examines patterns of transformation in three violent insurgencies: the Islamist insurgencies in Egypt (al-Jamaa al-Islamiyya) and Algeria (GIA/GSPC) during the 1990s and the violent campaign of the Shining Path in Peru 1980-2000, seeking to identify the mechanisms that continuously re-shape armed groups as well as the forms and targets of their violence. Adopting a relational approach that focuses on interactions between armed groups, their opponents, and local populations, it argues that the transformation of militant movements and their violent campaign is driven by a self-reinforcing dynamic of shifting relational configurations on the local level that determine patterns of support, control, and the balance of military power.