Comparison of clinical outcomes associated with different inhaler devices in Asthma and COPD patients. Asthma, COPD, MDI, DPI, Clinical Outcome. A prospective, observational study was conducted in a tertiary care teaching hospital among asthma patients and COPD patients for a period of six months. Data were collected using data collection form and Electronic Data Capture. Patients’ symptom control, Health Related Quality of Life, Feeling of Satisfaction with Inhaler were assessed with standard validated questionnaires. A checklist was provided to measure the correct inhaler technique. The patients were followed up in the end of 30 days, 60 days and 90 days and the scores were compared. A total of 213 patients out of 230 enrolled patients completed the study. It was observed that majority of Asthma and COPD patients were MDI users (68.42% & 81.02% respectively) than DPI users (31.58% & 18.98% respectively).The patients with Asthma used MDIs and DPIs equally with a less percentage difference. The patients with COPD used more DPIs than MDIs in the study. This study, draws a conclusion that Metered Dose Inhalers (MDI) and Dry Powder Inhalers (DPI) equally controlled the symptoms of patients with Asthma and COPD. Device satisfaction have proved to be a major assessing scale for drawing conclusions regarding device use in different diseases such as Asthma and COPD. The use of correct inhaler techniques directly aids to better symptom control, Qol and device satisfaction, which is due to the provided checklist analysis, ambulatory patient counselling and Pharmacists’ intervention in the hospital setting. The study could interpret that with better device satisfaction, patient can coordinate with the device technique which helps in better control of symptoms and ultimately both outcome control and Health Related QoL are equally improved.