In development studies with a focus on livelihoods, assets (also referred to as resources, capital, or means) represent a crucial dimension that influ- ences people's ability to secure a livelihood. Lack of access to land, water, or education often leads to poverty. The present paper summarises research findings from an international research network, the Swiss National Centre of Competence in Research (NCCR) North-South, regarding the crucial rela- tion between such assets and access to them. It brings together insights obtained in studies around the globe as to why some people are excluded from access to assets. Beyond this, it raises the question of whether gaining access is sufficient - does access to resources in itself lead to benefits, or do we need to broaden the concept of access? In addressing these and other questions, this review of NCCR North-South research embeds the concepts of assets and access within a broader understanding of contested politi- cal processes, informed by contemporary social science debates. In the concluding section, this enhanced understanding of social realities is con- trasted with social analyses underpinning (donor-supported) development interventions.