 Over the next 30 months he supervised some 55 volunteers working in agricultural cooperatives and credit unions serving the poorest.He returned home for graduate studies at the University of Wisconsin–Madison, obtaining an MA in Economic History (1970) and a PhD in Economic Development (1973).In between (1970–71) a Fulbright grant allowed him to spend two crop cycles as a hired labor to 30 peasant farmers in Peru, documenting the power and wisdom of their traditional farming practices.