The paper describes the recent evolution of cropping patterns in Kala, an agro-pastoral village in Central Mali, and examines the economic strategies of herders and farmers in the region. It looks at the growing competition between different groups for access to land and water in the context of (a) an increasing direct involvement by pastoral groups in cultivation, (b) the attraction of short-cycle crop varieties and the importance of manure and (c) the consequent desire of different groups to acquire and maintain control over water supply. It concentrates on the Bambara community of Kala, and the means by which it has asserted its right to control access to water by livestock within its territory so that farmers can acquire the manure they need to expand production of fast growing varieties of millet. This village's experience demonstrates some of the advantages of the integration of crop and livestock activities and points to the internal adaptability of traditional farming systems in a region where there are high production risks, due largely to climatic variability. The paper first describes the zone studied, socioeconomic aspects of the agro-pastoral system and the climatic context within which there has been a growing emphasis on rapid crop varieties. Some comparisons are made of returns to land and labour between short and longer cycle millet varieties. The sources of manure available to farmers are considered, and in particular the investment in digging wells by villagers in Kala is discussed. Finally, some of the consequences for the relationship between herders and farmers of the increased value of manure within the cropping system are discussed. (CAB Abstract)