The foreign-born inmate population in general, and the illegal alien and Mariel Cuban inmate populations in particular, have increased significantly since 1985. By law, immigration matters are a Federal responsibility. However, the States have increasingly been forced to accept the financial burden of incarcerating criminal aliens. During the 7-year period from 1986-93, the Department of Corrections spent approximately $1.23 billion to incarcerate foreign-born individuals. It cost slightly less than $0.5 billion to incarcerate illegal aliens during the same 8-year period. Although Congressionally mandated, the States receive no reimbursement for incarcerating illegal aliens and only partial reimbursement (approximately 4 percent of total costs) for incarcerating Mariel Cubans. These costs represent a burden on the States that should be addressed by the Federal Government either by providing full reimbursement or by accepting these criminal aliens into Federal custody. Tables