Zielstellung: Identifikation von Bedingungsfaktoren vorzeitiger Abbruche in der beruflichen Rehabilitation psychisch Kranker. Methode: 123 Rehabilitanden wurden prospektiv mehrdimensional untersucht. Ergebnisse: 23 Masnahmeabbrecher wurden identifiziert und konnten drei Gruppen (Exazerbation, Nichterscheinen, unspezifisch) mit differenziellen Bedingungsfaktoren zugeordnet werden. Schlussfolgerung: Berufliche Rehabilitation muss individuelle Personenmerkmale der Betroffenen starker berucksichtigen. Es sind integrative medizinisch-berufliche Konzepte zu fordern, die eine intermittierende Akutversorgung zwischenzeitlich erkrankter Rehabilitanden erlaubt. Objective: To determine the conditional factors underlying a premature termination of vocational rehabilitation programs. Methods: 123 rehabilitation participants were assessed prospectively regarding sociodemographic and psychopathological variables, level of functioning, subjective health, intellectual and work capacity. Results: 23 persons terminated rehabilitation prematurely. Drop-outs differed regarding sociodemographic and illness-related variables, in subjective physical health, level of functioning, intelligence and work capacity. Three types of „drop-outs” could be identified: Termination due to exacerbation (of a functional psychosis), due to reluctance to show-up (mainly men with antisocial personality disorders) and a non-specific group. Conclusion: Vocational rehabilitation of subjects with severe mental illness should take account of each rehabilitant's individual capacities and abilities as well as individual concepts of the disorder. Moreover, integrated concepts of medical treatment and vocational rehabilitation are needed to ensure rehabilitation success.