In response to a request from the owner of a Montessori day care facility, an investigation was conducted by NIOSH into possible causes of back pain and discomfort experienced among the workers. The staff included 22 teachers ranging in age from 23 to 53 years. Questionnaires completed by 18 workers were evaluated; 14 (78%) reported pain or discomfort at the neck/shoulder, back, hand/arm, or lower extremity. Most frequently reported was back pain (61%), followed by neck/shoulder (33%), lower extremity (33%), and hand/wrist (11%) pain. The employees caring for younger children tended to have more back complaints than those caring for the children aged 2.75 to 4 years. Posture analysis revealed that the teachers and aides spent about 25% of their time squatting, kneeling or sitting on the floor when working with the children. The teachers for the younger children assumed these postures 31% of the time, those with older children did so 18% of the time. They all spent an additional 25% seated on small wooden chairs designed for the children. The authors conclude that these workers were at increased risk of back and lower extremity musculoskeletal disorders. Many of these postures could be avoided simply by learning more ergonomically efficient techniques for accomplishing the same goals or completing the same tasks. Additionally, some changes should be made to the physical design of the work stations and equipment used by employees at the school.