We reviewed the literature on standard case management (SCM), intensive case management (ICM), assertive community treatment (ACT), and critical time intervention (CTI) for homeless adults. We searched databases for peer-reviewed English articles published from 1985 to 2011 and found 21 randomized controlled trials or quasi-experimental studies comparing case management to other services. We found little evidence for the effectiveness of ICM. SCM improved housing stability, reduced substance use, and removed employment barriers for substance users. ACT improved housing stability and was cost-effective for mentally ill and dually diagnosed persons. CTI showed promise for housing, psychopathology, and substance use and was cost-effective for mentally ill persons. More research is needed on how case management can most effectively support rapid-rehousing approaches to homelessness.