Contrary to a commonly held notion, scoliosis, and especially lumbar and thoracolumbar scoliosis, can develop during adulthood. Its evolution is slow and insidious and involves both the anatomic aspect of the curve and the functional aspect (development or worsening of painful spinal or radicular symptoms and/or disequilibrium). This finding underlines the necessity of a regular and extended monitoring of all patients presenting with such a condition. In terms of anatomy, three elements, each of them having a very precise functional impact, may characterize the radiological evolution of those deformities: the development of a rotatory dislocation, stiffness of the primary curve, and especially the lumbo-sacral spine, and the progressive development of a thoracolumbar kyphosis. Three types of treatment are available: rehabilitation, orthopedic treatment and surgery. The first two can act efficiently on painful symptoms and/or disequilibrium but in no case can modify the evolving pattern of the deformity. Surgical treatment is useful in stopping the evolving processes, reequilibrating the trunk on the pelvis and controlling painful lumbar and sometimes radicular phenomenon. Therapeutic and especially surgical indications are complex and by no means can be limited to an angle threshold beyond which surgery is indicated. Those indications depend on the type, the severity and the potential or effective evolution of the primary and compensatory curves, as well as on the age, the functional impact of the deformity and the general medical condition of the patient.