The rates of spontaneous remission and progression of dystonia to other sites were studied in 72 patients who first presented with adult-onset torticollis, and who were followed up for a mean of 7.7 years. Dystonia had progressed to sites other than the neck (mainly the face and upper limbs) in 23 patients (32%). The latter cases were not differentiated from those with isolated torticollis in terms of any of the demographic or clinical features studied, although they tended to have suffered from torticollis longer. Fifteen patients (20.8%) had experienced a spontaneous remission of their torticollis, which was sustained for a median period of 3 years in 9 cases (12.5%). Eighty-seven percent of the 15 remissions had occurred during the first 5 years of the illness. In the 9 cases with sustained remission, the duration of torticollis before spontaneous remission was significantly longer and remission had mostly occurred after 2 years of illness compared with the 6 who had relapsed. The 15 cases with spontaneous remission tended to have an earlier age of onset compared with those with no remission. Sixty-five percent of cases were correctly classified on the basis of age at onset, which emerged as the only salient variable in the discrimination of the 15 patients with spontaneous remission from the 57 without spontaneous remission. Age at onset, form of torticollis, gender, and direction of head deviation resulted in a correct classification rate of 70%, in the discrimination of the 9 cases with sustained remission from those with no remission.(ABSTRACT TRUNCATED AT 250 WORDS)