A special issue entitled “Longitudinal Research on Social Dynamics: The PSID at 50 Years” has recently been published by The ANNALS of the American Academy of Political and Social Science. In the introductory article “Fifty Years of the Panel Study of Income Dynamics: Past, Present, and Future”,David Johnson, Katherine McGonagle, Vicki Freedman and Narayan Sastry provided a detailed profile of PSID and illustrated its roles in longitudinal and life course research. Experts from various institutions also highlighted how PSID contributed to the studies in income volatility, child development, intergenerational mobility, health disparities, migration and aging in the past 50 years and offered insights into possible future directions.