This document discusses Farm Radio International's experience with participatory radio campaigns (PRCs) and what that means for agricultural extension services. It finds that PRCs are a highly cost-effective way to provide extension services, reaching an estimated 160 million farmer hours at a cost of $0.05 per hour. On average, PRCs cost $1 per farmer adopter to implement. The document attributes their success to factors like featuring local farmers, using dramatic storytelling techniques, and encouraging public adoption decisions. It concludes that PRCs should be expanded and that extension services need to better incorporate farmers' whole needs.