With a prevalence of up to 40%, back pain is one of the most common symptoms encountered in the doctor's office. Some 10% of the patients with severe pain become chronic cases. For the investigation of causal factors, the diagnostic work-up should cover not only somatic, but also (urgently) psychological, emotional and cognitive factors, as well as passive disease coping, depressive moods, and subjective attitudes to the condition. On the somatic side, overstraining of the muscles themselves, and lack of exercise play an important role. For the somatic work-up, the task is to search for pain triggers and secondary disrupting factors. Major clues are provided by the case history and an analysis of muscular status. For the identification of psychosocial factors, careful history-taking must be supplemented by simple psychological test instruments, such as Beck's depression inventory.