Access to energy is vital for sustainable development and poverty alleviation, yet billions of people in developing countries continue to suffer from constant exposure to open fires and dangerous fuels, such as kerosene. Renewable energy technologies are being acknowledged as suitable solutions for remote rural communities in much of the developing world and international development non-governmental organizations (NGOs) increasingly play important roles in the diffusion of these technologies via development partnerships. While these partnerships are widely promoted, many questions related to their functioning and effectiveness remain open. To advance the theory and practice, this interdisciplinary exploratory research provides in-depth insights into the nature of international NGO-driven development partnerships in rural renewable energy and their effectiveness based on the case studies in Talamanca, Costa Rica and Cajamarca, Peru.