A comprehensive system for the early rehabilitation of personnel has been developed and practised within the Finnish State administration since 1989. The rehabilitation process can be initiated as soon as the working capacity of a person or work community is threatened but is not yet seriously impaired. Rehabilitation is principally carried out on an outpatient basis alongside ordinary work. The aim of the study was to evaluate the outcomes and processes of early rehabilitation. The research data comprised several thousands of cases and consisted of a cross-sectional and a follow-up survey and a register-based follow-up. The surveys showed that during the rehabilitation period the average performance of the participants began to match that of the better-off non-participants, especially with respect to their general working capacity, mental well-being and occurrence of musculoskeletal problems. The sense of coherence rose in both groups, which can be partly attributed to positive changes in the workplace. In the group process, there also proved to be many factors contributing to achievement of the participants' rehabilitation objectives. The register-based follow-up showed that rehabilitation had a positive effect on average longer-term morbidity. In the cases of early retirement, the average retirement age of early rehabilitation participants was considerably higher than the average for the State sector as a whole. A system of outpatient early rehabilitation, where the rehabilitation programme and the development of working circumstances progress side by side, proved to give encouraging results at very moderate cost.