This book provides a comprehensive guide to collecting and managing farm-level agricultural data in developing countries. Many development workers face the need to collect data for planning, monitoring or evaluation of a project, or to use data collected by other people. The book explains how to plan, design and manage a survey, and introduces basic analysis and report writing. Unlike other books in this field, the authors deal with the statistical aspects of practical sample designs, and give worked examples to help the reader. The techniques and practical advice will help readers who are collecting data to improve the quality of their surveys and will help people who have to use data assess how reliable those data are.