Nongovernmental organizations (NGOs) are widely recognized for their success in designing and implementing locally effective natural resource conservation programs. However, most NGOs are small, scattered organizations that do not generate large-scale change. Some try to expand their operations, yet in the process lose the very attributes that fostered their local successes. This article examines how NGOs successfully achieve large-scale outreach, yet remain relevant to local needs. It draws on the experience of 168 NGOs from 42 developing countries that had expanded their natural resource program impacts, or that operated large, effective programs. It examines the complexities of the expansion process, identifies critical elements to consider in expansion efforts, and presents eight approaches used by NGOs that work well on a small scale yet can be transformed and incorporated into large-scale strategies, structures, and systems. --Journal abstract