This thesis documents the impact of development on Maasai masculine identities in Ngong, Kenya since the advent of British colonial rule in the country. The study mainly utilises the theoretical perspectives of postcolonialism and the theory of hegemonic and employs qualitative and to a lesser extent quantitative methods to explore the impact of the forces of modernization on dynamics of gender relations and masculine identities over this period. The study shows that the colonisation of the Maasai was rationalised on the rhetoric of development, as a civilizing mission where the colonial state saw itself as trustee of the Maasai people's interests. This entailed Othering their way of life and by so doing justifying their subjugation. The thesis shows that this notion of guided development led to the deployment of forces which have subsequently led to radical alteration the Maasai pre-colonial nomadic pastoral way of life and thus their livelihood strategies and their lifestyles. This notion of trusteeship has continued through colonial to postcolonial times. Development for the Maasai has meant their contact with forces of modernization such as western education and Christian religion and other cultural influences. The thesis establishes that these developmental endeavours have had far reaching consequences not only for their pastoral subsistence strategies but also for gender relations and masculinities in particular. Development is shown to have resulted in greater socio-economic stratification and to more distinct hierarchies of masculinities. It concludes by calling for caution when utilizing theories and concepts developed in the western context.