We report on two sisters with a childhood-onset form of predominantly axial dystonia with marked diurnal fluctuations. Onset of clinical features was at approximately 6 years of age. Associated features included marked fatigue, slight facial dysmorphism, short stature, obesity, and learning disability. Dystonia and fatigue responded to 3,4-dihydroxyphenylalanine (DOPA) therapy, with recurrence of symptoms upon withdrawal; the efficacy has been maintained over 7 years. Other symptoms were not influenced. There was no other case in the family (which included an older, healthy brother), except for non-specific fatigue without dystonia in the mother, and there was no significant family history except for obesity on the father's side. These observations are discussed in relation to the classical descriptions of Segawa syndrome, and to more recent reports of childhood onset, age-related, and transient benign paroxysmal tonic upgaze and ataxia. The combination of symptoms, their sensitivity to DOPA, and their persistence throughout childhood constitute, to our knowledge, a new clinical entity, which we propose to categorize as a DOPA-sensitive dystonia-plus syndrome.