IFSS offers data and tools for examining issues related to families and fertility in the United States spanning five decades. IFSS encompasses the Growth of American Families (GAF), National Fertility Surveys (NFS), and National Surveys of Family Growth (NSFG), as well as a single dataset of harmonized variables across all ten surveys. Analytic tools make it possible to quickly and easily explore the data and obtain information about changes in behaviors and attitudes across time.