We use an economy-wide model to analyze the effects of three broad programs to reduce illegal immigrants in U.S. employment: tighter border security; taxes on employers; and vigorous prosecution of employers. After looking at macroeconomic industry and occupational effects, we decompose the welfare effect for legal residents into six parts covering changes in: producer surplus and illegal wage rates; skilled employment opportunities for natives; aggregate capital; aggregate legal employment; the terms of trade; and public expenditure. The type of program matters. Our analysis suggests a prima facie case in favor of taxes on employers. (JEL J61, C68)