This article looks at how Maasai pastoralists are diversifying into different livestock and non-livestock responses to the fragmentation of traditional rangelands, climate stress, and restricted mobility. Unpredictable rains and extreme climate events are undermining the ecosystems that gave rise to pastoralist production systems. The Maasai are adopting new responses to secure their livelihoods, and these are strongly conditioned by existing patterns of social differentiation and power relations. The analysis moves beyond debates about the “peril to pastoralists” to look at how changing patterns of production, accumulation and agrarian politics impact on access to land and water resources, and how responses are conditioned by pre-existing patterns of social differentiation and land and resource use rules. Education emerges as a key variable, with younger Maasai men in particular “better placed to access information on and navigate changing rights-based access mechanisms” while making use of the “prevalent moral economy … to legitimize … claims to land allocation”. Younger Maasai women are also developing their own diversification responses but the same ‘moral economy’ excludes them from certain responses that depend on access to land and resources  – “gender, age, and education influence resource access as a ‘dynamic and constantly re-negotiated process’”.  The article also shows how adaptive customary systems are, with effective though not always equitable responses to changing conditions and opportunities. It has important implications for support programmes for pastoralists and for all societies where land and resource access is being renegotiated in response to climate, economic, and political changes.