Biofuel production has recently attracted a great deal of attention. Some anticipate substantial social and environmental benefits, while at the same time expecting sound profitability for investors. Others are more doubtful, envisaging large trade-offs between the pursuit of social, environmental and economic objectives, particularly in poor countries in the tropics. The paper explores these issues in Tanzania, which is a forerunner in Africa in the cultivation of a bio-oil shrub called Jatropha curcas L. We trace how isolated Jatropha biofuel experiments developed since their inception in early 2005 towards a fully fledged sectoral production and innovation system; and investigate to what extent that system has been capable of developing ...