The aim of this study was to evaluate the effectiveness of an asthma education programme in moderate and severe asthma patients in a longitudional, prospective and randomized study with a control group. Fifty-three asthmatic patients were studied, 26 of whom assigned to the educational group and 27 to the control group. The educational group attended the programme regularly for a period of 6 months. The programme included information about asthma, instruction on the appropriate use of medication and training in the metered dose inhaler (MDI) technique, and information about the identification and control of asthma attacks and the recongnition of early signs of exacerbation. The control group was submitted to the routine care provided at the Asthma Clinic, With no formal instruction regarding asthma control. The groups were identical with regard to severity parameters, skills, lung function and quality of life at the beginning of the trial. At the end of the study, the education group showed significant differences when compared with the group (education/control (meanvalues)) with respect to: visits to the asthma emergency room over the previous 6 months, 0.7/2 (p=0.03); nocturnal symptoms, 0.3/0.7 (p=0.04); score of symptoms, 1.3/2 (p=0.04). Improvements were also observed in skills and quality of life, knowledge of how to deal with attacks and how to control the environmental triggering factors, 73/35 (0.05); correct use of the MDI, 8/4 (0.001); understanding of the difference between relief and anti-inflammatory medication, 86/20 (0.05); and in the global limitation quality of life score, 28/50 (0.02). It is concluded that the educational programme led to a significant improvement in asthma morbidity and that the implantation of educational programmes is possible for special populations when these programmes are adapted to the socioeconomic profile of the patients, with a significant gain in terms of the reducion of symptoms and improved pulmonary function and quality of life of asthmatics.