A handful or studies in Somaliland have examined the prevalence and incidence of HIV among vulnerable women and their clients in Somaliland; however, the lack of clear population size estimates impedes the ability of stakeholders to undertake evidence-based planning. To ensure evidence-based policies, interventions and appropriate allocation of resources, an HIV mapping and size estimation of key populations at higher risk of HIV was conducted in Somaliland.  This study aimed to establish the location and size estimates of vulnerable populations and their clients in Hargeisa.