This report highlights trends in federal arrests and prosecutions by the country of citizenship of persons processed through the federal criminal justice system. It shows changes from 1998 through 2018. The report provides statistics on law enforcement and prosecutions along the U.S.-Mexico border, as well as in non-border areas. It shows the number of suspects arrested and prosecuted for both immigration and non-immigration offenses, including by their citizenship status. It details activities for all 94 federal judicial districts, while also separately detailing activities for the 5 districts along the U.S.-Mexico border. (See map on page 6.) The statistical findings in this report are based on data from the Bureau of Justice Statistics’ Federal Justice Statistics Program (FJSP). The FJSP receives administrative data from six federal justice agencies: the U.S. Marshals Service, Drug Enforcement Administration, Executive Office for U.S. Attorneys, Administrative Office of the U.S. Courts, U.S. Sentencing Commission, and Federal Bureau of Prisons. BJS links and standardizes this information to maximize comparability and to facilitate analysis across and within agencies over time.