This thesis examines the advocacy strategies of three Salvadoran non-governmental organisations (NGOs) aimed at contesting the Mano Dura gang policy and promoting the implementation of alternative forms of gang control. Introduced by the Flores administration in mid-2003, Mano Dura proposed to 'crack down' on the country's street gangs and foresaw the arrest and prosecution of suspected gang members on account of their physical appearance. Locally known as pandillas or 'maras', these groups allow marginalised youths to fulfil their need for friendship and respect, but, given their association with crime and violence, have developed into an important public security problem. This research explored how three NGOs sought to persuade the government to provide a comprehensive and rights-respecting response to gang activity and why these attempts remained relatively ineffective.