The aim of this qualitative PhD research was to fill identified gaps in knowledge, specifically, why do Somali female sex workers (FSW) in Nairobi, Kenya remain at high risk of HIV despite availability of targeted HIV prevention services. Globally, the evidence shows that sex workers are at higher risk than the general population, they have a disproportionate burden of HIV, and as a migrant group they may not have access to services. However, even with targeted services for sex workers, this group of migrant FSW was not accessing services. The research aimed to understand identity construction of Somali migrant FSWs, and how do risk environments and resilience amongst female sex workers who migrate affect health and health seeking behaviour. Throughout 2012-2013, the research team sought to interview migrant FSWs, through contacts with a Community Based Organization. The study was beset with challenges due to the changing security situation in Eastleigh. In total, 15 Somali FSWs were interviewed two to four times each, for a total of 50 interviews. Results are presented in three chapters, the first focuses on social networks and support; the second chapter on practices of routine discrimination and violence; and the third chapter looks at experiences of health services and health seeking behaviour. Somali FSWs in Nairobi are vulnerable and basic human rights not being met including the right to health, stemming from a lack of documented migration status, amongst other factors. FSWs experience systematic targeting by law enforcement, high levels of violence and harassment and lack of economic opportunities. Cultural factors, such as a religious context resulting in an external sense of control, assuming ‘Allah will fix it’, is compounded by exceptionally low self-esteem and a belief they are ‘bad Muslims’. Finally, their health seeking behaviour is poor, and oftentimes they simply cannot afford and do not prioritize their health over feeding and providing accommodation for their children. The primary implication for the research is that interventions need to go beyond biomedical sexual health and behaviour change campaigns to take into consideration the dynamics of intersectionality in the design and implementation of interventions.