This paper analyzes the development of research on reemployment services that has been shown to assisted unemployed workers return to work.  It follows rigorous research, mostly experimental work, that looks into the effectiveness of job search assistance and enforcement of the unemployment insurance work test, both of which have been shown to speed the return of unemployed workers to work.  It looks at what we have learned national evaluations such as the Charleston Claimant Placement Project, the New Jersey Unemployment Insurance Reemployment Demonstration Project, the Job Search Experiment conduct in the District of Columbia and Florida, the Maryland Unemployment Insurance Work Search Demonstration Project, and evaluations of the Work Profiling and Reemployment Services program.  It looks at the finding of state evaluations such as the Kentucky Worker Profiling and Reemployment Services Evaluation, the Nevada Claimant Employment Projects, the Remploy Minnesota Project, and the Washington Alternative Work Search Experiment.  Finally it examines research from other countries such as the United Kingdom Restart Evaluation and the Restart Experiment.  It sets the stage for more recent evaluations of the Reemployment and Eligibility Assessment programs that have been funded by the U.S. Department of Labor for implementation by states around the country.