Assessment systems are needed that are sensitive to employees' work performance as well as their need for support, while incorporating the input from both employees and their supervisors. This study examined the correspondence of one such evaluation system, the Job Observation and Behavior Scale (JOBS) and the JOBS: Opportunity for Self-Determination (JOBS: OSD), to establish whether performance and support evaluations administered by work supervisors would match self-determined perceptions of the same variables by sheltered and supported employees with disabilities. Results showed that JOBS ratings established by supervisors did not correspond closely to employees' self-determined ratings for any of the JOBS' subscales (Work-Required Daily Living Activities, Work-Required Behavior, and Work-Required Job Duties). Results also showed that employees consistently overestimated their work performance and underestimated their support needs relative to supervisors' ratings. These results suggest that major discrepancies exist between supervisors' and employees' perceptions of their work performance and support needs. These discrepancies may be important as job coaches, teachers, rehabilitation professionals, and employees and students with disabilities participate in employment preparation and transition planning. (Contains 3 tables.)