Terbutaline (Bricanyl) 0.5 mg t.i.d. administered via Turbuhaler was compared with fenoterol (Berotec) 0.2 mg t.i.d. administered via Inhalator Ingelheim in 36 asthmatic children aged 7-12 years. The study was of an open crossover design with two randomly allocated treatment periods, each lasting 2 weeks. Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were measured at clinic visits before study start and at the end of each treatment period. The patients recorded peak expiratory flow (PEF) before and after inhaler use, morning and evening. They also recorded asthma symptoms and number of extra inhalations. At the end of the study, children and parents were asked for inhaler preference. No differences between the treatments were found concerning the results of the lung function measurements at the clinic or at the PEF measurements at home. No differences were found between the treatments as regards asthma symptoms or number of extra inhalations. Two patients experienced mild side effects during fenoterol treatment, none during terbutaline treatment. Treatment with terbutaline in Turbuhaler was preferred by a majority of children and parents. In conclusion, in this group of asthmatic children, treatment with terbutaline administered via Turbuhaler was as efficacious as treatment with fenoterol administered via Inhalator Ingelheim. There was a clear preference in favour of the Turbuhaler.