This report in the Round Three Methodology Series provides readers with an introduction to the National Survey of America's Families, its sample design, data collection techniques, and estimation methods. An overview is also provided describing the survey's dual-frame design, the format of interviews, and the types of questions asked. In addition, the methods used to minimize errors and compensate for those that are unavoidable in data collection are described. Finally, the report presents information on the survey's resulting reliability--both in terms of sampling and nonsampling errors.