Elaborates strategies and a detailed plan of action for achieving the integrated delivery of health services, using the district health system as a model. The development of an integrated health system is put forward as a means of achieving greater access to care, increased participation, more equity, and enhanced effectiveness, particularly in situations where a critical shortage of resources forces planners to look for new, cost-effective solutions. Throughout the report, experiences from a range of countries are used to illustrate the obstacles to change as well as specific approaches that have the greatest chance of success. The report has six sections. The first, which establishes a framework for analysis, includes a tabular comparison of the advantages and disadvantages of vertical programmes and integrated health care services, and gives several examples of how integration actually works in practice. Additional background information is presented in the second section, which identifies the trends and factors that have encouraged efforts to integrate health services, particularly at the district level. Section three presents lessons about the effectiveness of different approaches. The most extensive section uses a systems approach to develop a new model of the district health system, focused on managed, comprehensive, and integrated primary health care, and including the complete integration of the hospital and its services. Having established a model, the report then considers the obstacles to change, the likely causes of failure, and the ways that these causes can be rationally addressed. The report concludes with a detailed, ten-step plan of action. Country experiences with integrated health systems are reported in an annex.