The integration of crop and animal production is well developed in the farming systems of Asia, particularly those in small-scale agriculture. There is marked complementarity in resource use in these systems, with inputs from one sector being supplied to others. Specific examples of the main crop–animal interactions are given for different countries, and reference is made to the results of a number of case studies. These have demonstrated the important contribution that animals make to increased production, income generation, and the improved sustainability of annual and perennial cropping systems.