Study Design. This study evaluated the long-term results of Klippel- Feil syndrome in patients with congenital scoliosis. Objectives. To determine the incidence of cervical and cervical-related symptoms of patients who have Klippel-Feil syndrome associated with congenital scoliosis. Summary of Background Data. Many authors have described the association of Klippel-Feil syndrome and congenital scoliosis. In this population of patients, cervical lesions often are discovered incidentally. The significance of these lesions is unknown. Methods. Thirty-two patients with congenital scoliosis and Klippel-Feil syndrome were observed for more than 10 years. They were questioned specifically about cervical and cervical-related symptoms. All patients had sequential cervical radiographs and physical examinations. Results. Despite rather dramatic radiographic appearances, only seven (22%) of the 32 patients had cervical or cervical-related symptoms, with two patients requiring surgery for their cervical lesions. The extent of the deformities and the average number of cervical vertebrae fused and cervical fusion patterns were statistically similar between the symptomatic and asymptomatic groups. Patients fused to the cervicothoracic junction for management of their deformities had a significantly increased incidence of cervical symptoms. Also, patients with congenital stenosis had a significantly greater incidence of upper extremity pain. Conclusions. Only a small number of patients with Klippel-Feil syndrome and congenital scoliosis developed cervical symptoms. No fusion pattern that placed the patient at greater risk for developing symptoms could be identified. Factors that did lead to a greater incidence of cervical symptoms were fusion to the cervicothoracic junction and congenital cervical stenosis.