In pursuit of peace and development, Article 41 of the UN Charter authorises the use of sanctions to deal with any state perceived as a threat to international security and peace. In the post-Cold War era, sanctions rapidly became a tool of choice for conflict prevention and peacebuilding. Nonstate armed actors (NSAAs) have increasingly become significant players in the international system as well as a target of sanctions. However, sanctions often fail to coerce NSAAs to end violence. NSAAs regularly ignore the demands of sanctions and engage the state and intervention forces in protracted wars. The literature on why sanctions fail betrays statist bias, emphasising the causal role of regime type, winning coalition, and vulnerability. State actors and NSAAs vary in nature, operational context, and modus operandi. Sanctions designed to alter the behaviour of state actors may not translate well to the context of NSAAs because they ignore the peculiarities of the latter. Peace and development are elusive where sanctions fail to effectively coerce NSAAs. The Revolutionary United Front (RUF) in Sierra Leone, and Union for the Total Independence of Angola (UNITA) in Angola are employed as case studies to explore the limitations of sanctions on NSAAs.