Shoulder joint dislocations collected from a randomized population were investigated in Sweden, wherein nearly 50% of people with primary dislocations never visit hospitals nor are treated by a physician. Thus information obtained from surgically treated patients is of limited value because cases requiring operative repair represent only a small and selected percentage of the population. The incidence of shoulder dislocation in people from 18 to 70 years of age was at least 1.7% and was three times more common in males. Spontaneous healing of recurrent dislocations in a period of many years was not uncommon. Shoulder joint dislocation was more common among children than was generally appreciated, with the prognosis usually good. Recurrences of primary dislocations in people 15 to 25 years of age were not as frequent as was expected.