A prospective randomised trial was performed to evaluate the effectiveness of an asthma education programme administered by an asthma nurse specialist in an out-patient setting. Sixty asthmatic patients (mean age 28.5 years) were enrolled, 30 to a usual care control group and 30 to an education group. The education group underwent an individual education programme lasting at least one hour. The following variables were measured at baseline, one month after the education programme and at one year follow-up: asthma knowledge by MCQ (36 point questionnaire), inhaler technique (7 point scale), peak expiratory flow rate (PEFR) and symptomatology by visual analogue score (0 to 10 score). The education group's inhaler technique and MCQ score both improved significantly at one month, from 5.4 (0.3) (mean [SEM]) to 6.5 (0.3), p < 0.001, and from 7.5 (2.4) to 22 (1.8), p < 0.0001 respectively. Both of these improvements were significantly greater than in the control group, and both were maintained at one year follow-up. The symptom score improved over one year in the education group, from 5.4 (0.6) to 7.6 (0.5), p < 0.05, and was unchanged in the control group. There was no change in the PEFR in either group. This study shows clear objective benefits to an out-patient asthma education programme conducted by an asthma nurse specialist.