[영문]I especially wish to thank David Card for his advice and encouragement. I also thank John Abowd, Alan Auerbach, Richard Blundell, Kenneth Chay, Todd Elder, Kevin Hallock, Hilary Hoynes, Roger Koenker, Jonathan Leonard, Steven Levitt, Enrico Moretti, James Powell, two anonymous referees, and many seminar participants for their advice. I owe a special thanks to Bhashkar Mazumder, Lynn Riggs, and the staff members at the Center for Economic Studies at the U.S. Census Bureau and at the California Census Research Data Center (CCRDC) for their help in facilitating my use of the confidential data. Financial support from the Robert Burch Center for Tax Policy Analysis, the Center for Labor Economics, the Institute for Industrial Relations at the University of California, Berkeley, and the CCRDC is gratefully acknowledged. The research in this paper was conducted while I was a research associate at the CCRDC in association with the Center for Economic Studies of the U.S. Census Bureau. Research results and conclusions are my own and do not necessarily indicate concurrence by the U.S. Census Bureau, the Center for Economic Studies, or the CCRDC.I use longitudinal earnings data from Social Security records to study the effect of selective emigration on the measured progress of immigrants to the United States. The immigrant-native earnings gap closes by 10?15 percent during immigrants' first 20 years in the United States, or about half as fast as typical estimates from repeated cross sections of the decennial census. The divergent results indicate that emigration by low-wage immigrants has systematically led past researchers to overestimate the wage progress of immigrants who remain in the United States. Selective back-and-forth migration also leads typical estimates to overstate the measured decline in earnings among successive immigrant arrival cohorts between 1960 and 1980.