Rajesh Tandon and Budd Hall, the UNESCO Co-Chairs in Community-Based Research have worked together on the theory and practice of participatory research since they first met in Caracas, Venezuela in 1978. This article is a conversation between the two of them that took place in New Delhi, India in 2015. It covers the creation of the concept of participatory research, a coming to awareness of the importance and power of local knowledge, the creation of the International Participatory Research Network and their thoughts on some of the challenges facing community and academic partners today. Of note is the fact that the early roots of participatory research were found in the global South, specifically in Africa, Asia and Latin America. Of further interest is the fact that for the first 20 to 25 years, participatory research was a discourse located almost entirely outside formal academic circles but rather in social movement structures and civil society circles.