This article examines the recent uptake of tractor ploughing services in northern Ghana. It examines the historical continuities in mechanisation and the emergence of a class of medium-scale commercial farmers. In the light of this, it questions the thesis that the recent uptake of mechanisation and emergence of medium-scale farmers reflects the successes of market liberalisation. It is critical of neoclassical theories of agricultural transformation rooted in theories of induced innovation and argues for a political economy approach that links agricultural transformation to processes of social differentiation and the historical role of the state in promoting agricultural commercialisation.