Across Canada, and in many places around the world, cooperative management arrangements have become commonplace in land and resource governance. The Stein Valley Nlaka’pamux Heritage Park, located in south-central Interior British Columbia, is one such example. An unlogged, undammed watershed, the Stein Valley became the site and subject of protests over proposed logging between the 1970s and 1990s. It lies within the territories of the Nlaka’pamux Nation and, since its park designation in 1995, has been jointly managed by the Lytton First Nation and the Provincial Government through a Cooperative Management Agreement. This thesis traces human-land relations throughout the history of the Stein Valley in order to theorize an expanded conception of co-management. The central goal is to understand how various co-management arrangements are formed, contested, and enacted through particular land-use practices, social and institutional interactions, and socio-ecological relationships. Through a detailed reading of the socio-ecological history of the Stein Valley, drawn from semi-structured interviews and a literature survey, this thesis adds to existing scholarship on B.C. environmental politics. In this project, I locate various co-management practices at work in the Stein Valley region—including but not limited to practices of use, stewardship, and governance compelled by legalistic co-management arrangements. Ultimately, this thesis calls for a closer examination of the myriad of practices and relations embedded within land and resource management regimes. In doing so, it resituates the agency of various actors, and their ecological interactions, in producing, governing, and shaping the socio-ecological landscapes we both inhabit and actively create / Graduate