The increase in collaborative projects involving American Indian tribes and natural resource management agencies in the United States reflects two emergent trends: 1) the use of collaborative approaches between agencies and groups in managing natural resources; and 2) the concurrent increased recognition of American Indian rights, institutionalization of consultation processes, and a general movement of Indian self-determination. This article focuses on institutional mechanisms that bring together tribes and natural resource management agencies in collaborative processes to achieve mutually desired resource management objectives. Using qualitative analysis of data from ten collaborative projects across the United States, we identify attributes of collaborative arrangements emerging from tribal–federal collaboration: decision-making authority; transfer of funds from agency to the tribe(s); the level of mutual dependency; the sharing or transfer of various forms of knowledge, including scientific and cultural; and responsibility for conducting management field work. Examining the similarities and differences across the attributes, we characterize the projects into five types (co-management, contractual, cooperative, working relationship, and conservation easement), and find that considerable variation exists in the forms and functions of tribal–federal collaborative arrangements. We explore two types of collaborative arrangements in more depth to better understand what factors influence the integration of traditional ecological knowledge. Comparing gray wolf (Canis lupus) recovery in Idaho and forest restoration in northern California, we find that traditional ecological knowledge was a key factor in initiating both collaborative projects, but also that the application of traditional ecological knowledge on-the-ground differed.