The prognosis of allergic rhinitis was studied in 154 children aged 3-17 years at diagnosis by means of a detailed questionnaire administered 8-11 years later. The symptoms had completely disappeared in only 15 (10%) patients. The conjunctival symptoms, however, had disappeared or were controlled successfully by topical drug therapy in almost all, and 77 (50%) were managing without medication for allergic rhinitis. Twenty-five (23%) of the 110 children with seasonal allergic rhinitis had a perennial disease at follow-up, in contrast to seven (16%) of 44 with perennial allergic rhinitis originally who had only seasonal symptoms at follow-up. Asthma or wheezing had developed in 29 cases (19%) and was more common (p less than 0.01) among those with perennial allergic rhinitis (15 of 44) than among those with seasonal allergic rhinitis (14 of 110). No significant association was found between age at onset of symptoms, family history of atopic disease or type of treatment for allergic rhinitis and allergic rhinitis still present at follow-up or development of asthma during the observation period.