Seventeen Justice Reinvestment Initiative states are projected to save as much as $4.6 billion through reforms that increase the efficiency of their criminal justice systems. Eight states that had JRI policies in effect for at least one year Arkansas, Hawaii, Louisiana, Kentucky, New Hampshire, North Carolina, Ohio, and South Carolina reduced their prison populations. Through the Initiative, states receive federal dollars to assess and improve their criminal justice systems while enhancing public safety. This report chronicles 17 states as they enacted comprehensive criminal justice reforms relying on bipartisan and interbranch collaboration. The study notes common factors that drove prison growth and costs and documents how each state responded with targeted policies.