Abstract Introduction Asthma and COPD are respiratory diseases in which a better knowledge and understanding of the pathology allows the patients to be more involved, which is crucial in their treatment. Holding educational sessions is a good way of imparting information to the patients. Aim To determine the efficacy of educational sessions in helping patients with asthma and COPD to acquire a better understanding of their condition. Methods Following a Portuguese Lung Foundation initiative to improve knowledge about respiratory health, educational sessions for patients suffering from asthma or COPD were organized. 25 randomized patients with each disease were invited to participate. Each session lasted 60min. Patient knowledge was tested by means of a multiple choice questionnaire before and after the session. Results Fifteen patients with asthma attended the sessions; they had an average age of 36 years, of which 60% were female. Within the group 60% were able to name their pathology correctly. Seventeen patients with COPD attended the sessions; they had an average age of 69 years, of which 70% were males and only 3 (17.6%) patients were able to correctly name their pathology. In both groups, there was a statistically positive improvement (p<0.05) of correct answers to the questionnaire at the end of each educational session. Conclusion Patient knowledge increased in each educational session. Patients with COPD were less well informed about their disease than patients with asthma and they also had more difficulty in correctly naming their disease.