The focus of this paper is the process of adjustment of farm performance to disequilibrium with new technology over time, which has been a subject of speculation till now. It shows that, left to learn from their own experience, farmers will be slow to realise the full technical potential of a new technology. Drawing on theories of intra-firm diffusion, the hypotheses tested in this paper using data from India are: (1) initial overall farm performances are characterised by modest and widely varying technical and allocative efficiencies, and (2) over time, average efficiencies rise. © 2001 Elsevier Science B.V. All rights reserved.