Since Independence the Kenyan economy has witnessed extensive and rapid commercialisation of both the commodity and labour markets. Although there has been much discussion of this process, its impact on the efficiency of resource allocation in peasant agriculture has hitherto been neglected. The author argues that efficiency has not been achieved mainly because contractual constraints have prevented market transactions from having the corrective effects predicted by economic theory. He concludes that absentee land ownership lies at the root of much of this malfunctioning and that a redistribution of land entitlements is required to reduce poverty and increase national output. -from Author