SUMMARY British morbidity statistics are reviewed to try to estimate the size of the problem of the painful back. National Insurance figures yield an estimated 13.2 million working days lost in one year, though only 68% of this is identified in routinely published statistics. Other bodies of data (G.P. consultations, outpatient and inpatient flows, spinal supports supplied) indicate use of services by sufferers. The difficulties in retrieval caused by the structure of the International Classification of Diseases (ICD) and the effects of the latest revision of it are examined