Data sources that can be used for studies of health expectancy are abundant. This chapter provides an overview of many of these data sources, along with links to websites that contain documentation and instructions for accessing the data. The chapter discusses the two main types of data that are used for analyses of health expectancy-cross-sectional and panel-and reviews the most common measures that have been used in health expectancy research: self-rated health, disability and functional limitation, chronic conditions and diseases, cognitive impairment and dementia, and psychological well-being. A variety of types of data sources, including surveys, censuses and administrative data are covered. The focus is on data sources that can be used for cross-national comparisons and/or analyses of trends over time and for which data are publicly available.