Participatory approaches to project planning and implementation have been hotly debated in development cooperation and policy circles since the 1980s. This book contributes to the debate by focusing on international, development-oriented agricultural research. Based on fieldwork in rural northern Vietnam and interviews with researchers in Vietnam and Germany, the book analyzes the manifold meanings associated with the concept of participatory research, and the hurdles participatory research must overcome in practice. It demonstrates the need to recognize multiple meanings of 'participation' in a multicultural actor constellation, the importance of political and research institutions in governing researchers' work, and the potential of participatory methods to contribute to ethically and methodologically sound research practice.