This thesis examines how migrants have sought to develop and use network social capital as a survival strategy on high risk migration routes a nd to facilitate integration into their host society. It focuses on the Sahara Desert context, which has been increasingly marked by intensified enforcement and risk to migrants amid the European Union’s externalisation of migration control policies, actin g with sending and transiting third countries in the African Union. The thesis draws on original field research involving interviews with 101 migrants who had the experience of travelling high risk migration routes through the Sahara Desert. It also draws on interviews with 16 humanitarian organisation staff members working with migrants in these regions. Respondents identified several factors motivating efforts to derive network social capital that were central to their survival approaches. Leading factors included having limited resources, having no contacts at the intended destinations, lacking knowledge of migration routes, travelling alone and vulnerability to authorities, human smugglers and other actors. Each of these factors spurs them to derive network social capital in ways that include forming groups, humanitarian organisations, human smugglers, informal labour networks, social networking applications and the support of kinship connections. This thesis thus makes a significant contribution to the understanding of migrant agency, challenging some still prevailing views of migrants as primarily threats or victims and instead presenting migrants as resilient survivors. It also situates their exercise of agency within the broader empirical and theoretic al framework of increasing state securitisation of migration and their growing extraterritorial enforcement efforts. It works to advance understanding of the full implications of such policies while providing a fine grained counter narrative on them from migrants’ contextually situated perspectives.