The U.S. Census Bureau produced estimates of net international migration from 2000 to 2010 for the 2010 Demographic Analysis (DA). Foreign-born immigration is a large component of net international migration and is estimated using data from the American Community Survey (ACS). The coverage of recent foreign-born immigrants in the ACS is unknown, and undercoverage may result in an underestimate of foreign-born immigration. Currently, we assume that undercoverage of foreign-born immigrants in the ACS is accounted for through the application of weights and population controls, but the ACS is only controlled by age, sex, race, and Hispanic origin, and not nativity. In this working paper we present results from our research examining the coverage of the foreign-born population in the ACS. Using data from the 1) Census 2000, 2) Accuracy and Coverage Evaluation (A.C.E.) program, and 3) Census 2000 Supplementary Survey (C2SS), we developed coverage factors. In this paper, coverage factors refer to adjustment factors to account for the coverage of the foreign-born population in the ACS. We then applied the coverage factors to annual ACS data from 2001-2009 to produce alternative estimates of foreign-born immigration. The strengths and limitations of this methodology are discussed as well as our overall estimates of coverage of the foreign-born in the ACS.