Assertive community treatment (ACT) is one of the most well-validated treatment models for people with severe mental illness, and ACT is one of the few evidence-based practices that is widely implemented in community mental health programs; however, existing ACT approaches have little impact on functioning. The ACT model provides a unique opportunity for implementation of recovery-oriented EBPs throughout community mental health programs in the US. This project will examine the incremental effectiveness of implementing cognitive-behavioral strategies and social skills training in ACT relative to ACT, alone. The investigators will begin to examine a potential mechanism of change involving defeatist performance beliefs that can interfere with performance of community functioning behaviors, and will use qualitative methods to identify barriers and factors that contribute to successful implementation.