Spondylolysis was found in 25 of 46 spines of Eskimos from Greenland, at L1 in one case, at L3 in five cases and at L4 and L5 in 14 cases each. Two spondylolytic vertebrae were seen in the same spine in nine cases. Among young individuals, spondylolysis was found in 2 out of 15 spines and in older in 23 out of 31. The prevalence of spondylolysis was higher, the fourth vertebra was more commonly affected, and spondylolysis occurred at an older age in Eskimos than in other ethnic groups.