The effect of patient education on steroid inhaler compliance and rescue medication utilization in patients with asthma or chronic obstructive pulmonary disease (COPD) has not been previously investigated in a single study. We randomized 78 asthmatics and 62 patients with COPD after ordinary outpatient management. Intervention consisted of two 2-h group sessions and 1 to 2 individual sessions by a trained nurse and physiotherapist. A self-management plan was developed. We registered for 12 mo medication dispensed from pharmacies according to the Anatomical Therapeutic Chemical (ATC) classification index. Steroid inhaler compliance (SIC) was defined as (dispensed/prescribed) x 100 and being compliant as SIC > 75%. Among asthmatics 32% and 57% were compliant (p = 0.04) with a median (25th/75th percentiles) SIC of 55% (27/96) and 82% (44/127) (p = 0.08) in the control and intervention groups, respectively. Patient education did not seem to change SIC in the COPD group. Uneducated patients with COPD were dispensed double the amount of short-acting inhaled beta(2)-agonists compared with the educated group (p = 0.03). We conclude that patient education can change medication habits by reducing the amount of short-acting inhaled beta(2)-agonists being dispensed among patients with COPD. Educated asthmatics showed improved steroid inhaler compliance compared with the uneducated patients, whereas this seemed unaffected by education in the COPD group.