The lives of indigenous and other peoples who depend heavily on their physical environments are intimately linked to the conservation of biodiversity. This chapter presents an overview of the ethnobiological research that has explored those links. We begin with a discussion of traditional ecological knowledge (TEK) and its relationships to biodiversity conservation. Local knowledge of the environment, traditional management practices, social institutions that guide resource use, and worldviews are integral and overlapping components of TEK and shape its relationships to conservation. Most TEK systems are dynamic and adaptive, and their focus on maintaining ecological processes and regeneration cycles have allowed many of them to sustain local biodiversity over long periods of time. The relationships between TEK and conservation are also complex, as TEK is heterogeneous within and across communities and influenced by socio-economic, political and cultural factors. Today the economic dependence of many local communities on the commercial extraction of wild resources presents both opportunities and challenges for biodiversity conservation. Participatory ethnobiological approaches that more fully integrate the social and ecological sciences will help provide a better understanding of the links between the conservation of biological and cultural diversity, and of how TEK can be better integrated into conservation plans and policies.