Previous investigations have identified staff beliefs about barriers to implementing behavioral interventions in programs for persons with severe mental illness. One of these barriers, institutional constraints, was found to be associated with collegial support; i.e., staff who report more collegial support were less likely to endorse institutional constraints. The purpose of this study was to determine how the components of collegial support were associated with beliefs about institutional constraints. Fifty-six staff members completed measures of staff opinions about barriers to implementing behavior therapy, satisfaction with collegial support, source of support, and functions of support. Results suggested that collegial support is significantly associated with co-worker and supervisor support, but not the support of family and friends. Endorsing institutional constraints was inversely associated with the support of co-workers and supervisors; institutional constraints were positively associated with the support of family and friends. Endorsing institutional constraints was also inversely associated with the sense that others rely upon the individual for their well-being. Implications of these findings for diminishing barriers to behavioral interventions are discussed.