Pain drawings were obtained from two groups of patients and one of nonpatients, in a total of 264 subjects, all suffering from back pain. The pain drawings were rated in four grades according to the degree of nonorganic and extended pain. The reliability was excellent with an intra- and interrater agreement of 80 and 70%, respectively. Three quarters of the nonpatient group had dull aching pain in the lower back only, whereas widespread or nonanatomical pain was prevalent in patients responding poorly to treatment. A correlation was also found to ethnic background and social situation but not to alcohol abuse or psychiatric illness. Pain drawings afford an important clue to nonorganic factors in the assessment of back pain.