Inhaled medication is important in the treatment of chronic obstructive pulmonary disease (COPD). In this paper a comparison of the long-term efficacy of three instruction-modes is presented. A total of 152 COPD-patients were randomized into one of four groups: Personal-, video-, group-instruction and a control group. Inhalation technique was assessed by means of checklists, on which essential inhalation manoeuvres were identified. Up to 9 months later, 148 patients returned for follow-up assessment. Prior to instruction 61% of patients in the control group had a perfect score on essential actions, compared to 62, 65 and 53% for those receiving group-, personal- and video-instruction respectively. At follow-up these percentages were 49, 97, 75 and 76%. For group-(35%) and video-instruction (24%) the increase from baseline was significant. Examining the different inhalers under investigation, it is striking, that only 24% of all patients with a Metered Dose Inhaler (MDI) performed all essential checklist items correctly, versus 96% for those using a Diskhaler. The fact that for the MDI this percentage improved to 90% post-instruction, shows that time spent on instruction, is time well spent. We conclude that group instruction seems superior to personal counselling, and equally effective or even better than video instruction. Personal instruction should not be dismissed and a combination with video instruction might prove to be effective as well.