Jules Siedenburg (in this issue of DPR) has misunderstood the purpose of our 1994 book, which was to differentiate between long-run forces of change and the impact of particular projects. The methodology we adopted is rehearsed in this response, as it authenticates our data. His attack on our...

This article describes the chief findings of research carried out in four African dryland areas to investigate the validity of the authors' 'Machakos hypothesis', and to derive lessons on appropriate enabling policies. The findings were subsequently submitted to in-country validation and...