Two methods of administering nebulized bronchodilator solution were compared in 15 patients with chronic airflow obstruction. There was no significant difference between facemask and mouthpiece as far as breathlessness, wheezing or improvement in peak expiratory flow were concerned. Ten patients preferred facemasks, three preferred mouthpieces; two preferred mouthpieces except when severely breathless, when they preferred the facemask. It is suggested that the patients be allowed to use either mask or mouthpiece depending on their preference.