In 1989, a group of researchers, farmers and farm advisors initiated an interdisciplinary study of the transition from conventional to low-input and organic management of a 4-year, five-crop rotation. Crop yields initially varied among systems, but now appear to be approaching each other after a transition period that included the development of practices and equipment most appropriate for each system. Farming practices and crop production costs are carefully documented to compare the various systems' economic performance and biological risks. Supplying adequate N and managing weeds were challenges for the low-input and organic systems during the first rotation cycle, and experiments are being conducted on an 8-acre companion block to find solutions to these and other problems. Leading conventional and organic growers provide a much-needed farmer perspective on cropping practices and economic interpretations, because we try to provide “best farmer” management of each system. Research groups within the project are focusing on soil microbiology, economics, pest management, agronomy and cover crop management.