Ninety seven outpatients with schizophrenia spectrum disorders (SSDs) were randomly assigned to the Walk, Address Sensations, Learn About Exercise, Cue Exercise Behavior for SSDs (WALC-S), a motivational intervention designed to increase exercise in SSDs (n = 48), or a time and attention control group (TAC, n = 49). WALC-S and TAC groups met weekly for 4 weeks before a 16 week walking program was offered to all subjects. We compared the exercise attendance, persistence and compliance of the groups during the walking program. WALC-S recipients attended more walking groups, for more weeks and walked more minutes than those receiving TAC. Percent of WALC-S or TAC groups attended was significantly correlated with overall attendance (r = 0.38, P = 0.001) and persistence (r = -.29, P = 0.01), as well as number of minutes walked. This study is among the first to examine interventions designed to enhance exercise motivation in SSDs.