Participatory cassava breeding is being done with two communities in Ghana; at Nkaakom in the forest zone and at Aworowa in the forest transition zone. The collaboration required a team of scientists and was initiated with village surveys on cassava production, consumption and marketing, followed by interviews of other cassava stakeholders from University researchers to private-sector processors. Cassava seeds obtained from superior, cassava mosaic disease-resistant landraces and varieties were direct-planted in communal plots. Scientists monitored growth and any pest and disease attacks monthly until harvest one year later. Farmers monitored crop growth informally and during field days. At harvest, many of the seedlings yielded several times the national average yield and many remained free of cassava mosaic disease. Both farmers and scientists selected plants to provide cuttings for further trials: about 60% of the selections of the plant breeder and the farmers were in common.