Homeless people with mental health problems are a particularly vulnerable population whose integration into the community results very difficult. This article reviews relevant studies about the effectiveness of different kinds of intervention on homeless people with mental health problems and/or alcohol and drug abuse. Although the comparison of the reviewed studies is not straightforward, case management and assertive community treatment emerge as particularly effective interventions to improve the housing conditions of people with mental health problems. The benefits of these strategies are questionable in other areas such as mental health or substance misuse.