Supported employment for people with severe mental illnesses is an evidence-based practice, based on converging findings from 4 studies of the conversion of day treatment to supported employment and 9 randomized controlled trials comparing supported employment to a variety of alternative approaches. These two lines of research suggest that between 40% and 60% of consumers enrolled in supported employment obtain competitive employment while less than 20% of similar consumers do so when not enrolled in supported employment. Consumers who hold competitive jobs for a sustained period of time show benefits such as improved self-esteem and better symptom control, although by itself, enrollment in supported employment has no systematic impact on nonvocational outcomes, either on undesirable outcomes, such as rehospitalization, or on valued outcomes, such as improved quality of life. The psychiatric rehabilitation field has achieved consensus on a core set of principles of supported employment, although efforts continue to develop enhancements. A review of the evidence suggests strong support for 4 of 7 principles of supported employment, while the evidence for the remaining 3 is relatively weak. Continued innovation and research on principles is recommended.