The Panel Study of Income Dynamics (PSID) is the world's longest running household panel survey. With five decades of data collected on the same families and their descendants, the PSID is a cornerstone of the data infrastructure for empirically-based social science research in the U.S. and the world. With its long-term measures of economic and social wellbeing, the study has allowed researchers and policy analysts to investigate the dynamism inherent in social and behavioral processes. The long panel, genealogical design, and broad content provide scientists a unique and powerful opportunity to study evolution and change within the same families over decades. The impact of the PSID is substantial with over 4,000 peer-reviewed publications based on the data, including nearly 900 dissertations. At least nine federal agencies utilize the PSID to fulfill their missions and NSF named PSID one of its 60 most significant discoveries in its first 60 years of existence.