Current and former professional staff of the Population Council have updated the Handbook for Family Planning Operations Research Design. They assume that readers of the handbook already know terms and concepts of research design and statistics and have some field research experience. The primary objective of the manual is to provide guidance to health and family planning researchers to develop and write and detailed operations research proposal. In fact, it can be and has been used in workshops on research proposal writing. It also serves as a means for program administrators and managers to understand the workings of operations research and the application of research findings for improving service delivery. The authors draw from their field experiences from Asia, Africa, and Latin America. The handbook begins with a definition of operations research, its objectives, different types of operations research, and its desing. It guides readers on how to identify, define, and justify the research problem. Further it helps them to choose a strategy to solve the problem. I next covers objectives and hypotheses of the research. The handbook makes the readers aware of the need to describe the proposed intervention and to define variables and terms. It spends a considerable number of pages on study design including the different types of designs. It also provides guidance on sampling and data collection. The handbook gives detailed guidance on data tabulation and analysis. It also stresses the need to disseminate and use the research findings. It encourages researchers to list limitations of the study, resources, and facilities. It also addresses the preparation of appendixes, title page, and abstract.