The work in school kitchens has changed dramatically during the past decade. The food-processing has been rationalized, the work tasks have been reorganized, and the productivity demands have increased. According to the personnel, the mean age of kitchen workers has risen and their work ability has decreased. In this study, a long-term program for maintaining the work ability of kitchen workers was created, evaluated and developed further. The study population included all the kitchen workers (n = 198) in Espoo, the second largest city in Finland. The mean age of the workers was 44.8 years in 1997, and 98% of them were women. The three-year participatory intervention was started in 1997. It consisted of several activities supporting professional competence of employees'. The participants improved their work process in groups and participated in vocational training, as well as in a fitness program. The management also reorganized its own work and became acquainted with, e.g. age management. Both before and after the intervention, the Work Ability Index (WAI), the Occupational Stress Questionnaire (OSQ) and a measure of conceptual mastery of kitchen work were administrated to evaluate the effects of the program.