The United States has the highest incarceration rate in the world—a rate five to ten times higher than those of countries like Canada, France, and the UK. A culture of punishment, combined with race- and class-based animus, has led the United States to rely on incarceration more heavily than any other country in the world does. The politicization of criminal justice policy and a lack of evidence-based assessment result in a one-way ratchet in which law and policy grow ever more punitive. The human and financial costs of mass incarceration are staggering, and the burden falls disproportionately on the poor and people of color. However, the recent fiscal crisis and years of falling crime rates have combined to create the best opportunity in decades to challenge our nation’s addiction to incarceration.