Since the early 1980s, supermax incarceration has emerged as a common feature of the American corrections landscape. This special type of high-cost housing, which involves extended isolation with little programming or contact with others, remains largely unevaluated and is of interest for three reasons. First, the study of supermax housing offers a unique opportunity to understand the factors related to the successful reentry of offenders back into society. Second, it affords an opportunity to test the claims, many of which are grounded in mainstream criminological theory, that have been made about the putative effects of supermax confinement. Third, it provides an empirical touchstone that can help inform policy debates about the merits of such confinement. Examining data from the Florida Department of Corrections, we test competing hypotheses about the effects of supermax housing on 3-year recidivism outcomes. We find evidence that supermax incarceration may increase violent recidivism but find no evidence of an effect of the duration of supermax incarceration or the recency of such incarceration to the time of release into society. We discuss the findings and their implications for theory, research, and policy.