The authors wish to acknowledge the indispensable assistance of Dr Richard Laing, Associate Professor at the Boston University School of Public Health (BUSPH), who assisted in the writing of the original proposal and this paper. The authors would also like to thank Sarah Richards of BUSPH, who was instrumental in choosing, designing and undertaking research with the Cameroon Baptist Convention (CBC), and Lucy Honig for all her help in writing this report. At the CBC, the authors thank Pius Muffih Tih, Director of Health Services, as well as Richard Tambe, Head Pharmacist, and Kathy Kroll, Head Nurse, without whose suggestions and support the results of the study would have been negligible. Thanks are due to Dr Davidson Hamer of the Harvard Institute for International Development and New England Medical Center who donated immunizations to the authors and Ralph Timperi, Assistant Commissioner of the State Laboratory Institute, Department of Public Health, Massachusetts, who donated several computers and other equipment to the CBC. And we should like to express our deep gratitude to the personnel of the CBC health facilities who accommodated us in their facilities, their offices and their homes.

Finally we wish to thank Daphne Fresle and Hans Hogerzeil of WHO's Action Programme on Essential Drugs (DAP) for their very helpful comments on earlier drafts of this report and to Kath Hurst (DAP) for final editing and seeing it to press.