ports the results of research and analysis undertaken by U.S. Census Bureau staff. It has undergone a Census Bureau review more limited in scope than that given to official Census Bureau publications. This document is released to inform interested parties of ongoing research and to encourage discussion of work in progress. The views expressed herein are attributable only to the authors and do not represent the views of the U.S. Census Bureau, its program sponsors, Cornell University, or data providers. Some or all of the data used in this paper are confidential data from the LEHD Program. The U.S. Census Bureau supports external researchers' use of these data through the Research Data Centers (see www.ces.census.gov). For other questions regarding the data, please contact Jeremy S. Wu, Program Manager,

Confidentiality-protected and integrated employer-employee microdata—including worker and firm demographics, worker attachments to firms, earnings, and precise coding of location of place of work and place of residence—have been used to investigate a variety of questions in economics and demography. The rich geographic dimension of these integrated microdata, however, has yet to be fully exploited by the regional science community. This article describes the structure, applications, and confidentiality protections of integrated employer-employee microdata housed at the Longitudinal Employer-Household Dynamics (LEHD) Program at the U.S. Census Bureau. The LEHD Program makes use of administrative records from nearly the entire universe of existing firms and workers for forty participating states. The broad coverage of economic agents in conjunction with the precise coding of geography makes the data particularly suitable for addressing issues in urban and rural economic development, agglomeration and growth, economic geography, and spatial econometrics.