We examined burnout and job satisfaction among 216 case managers serving clients with severe mental illness, comparing assertive community treatment (ACT) workers with traditional case managers (TCMs) in two Midwestern states. Compared to TCM, ACT workers reported significantly lower levels of burnout, higher levels of job satisfaction, and more favorable perceptions of their work environment. In the TCM sample, length of time in current job was associated with greater burnout, and severity of client problems was associated with greater burnout and job dissatisfaction. Neither of these sets of factors predicted burnout in the ACT sample, however. Instead, no case manager characteristics, caseload characteristics, or service delivery variables, except for age, predicted burnout in the ACT sample. The findings suggest that the ACT model may be especially suited to protect against burnout in case managers serving clients with the most severe disabilities and who are most prone to psychiatric readmissions. However, the small effect sizes and the lack of a prospective, experimental design suggest that further research is needed before drawing firm conclusions.