Chronic obstructive pulmonary disease (COPD) and asthma are airway diseases with acute exacerbations. Natural course of both disease are affected by exacerbations. COPD exacerbations may be caused by infections and other causes; indoor and outdoor pollution, cardiovascular diseases, asthma-COPD overlap syndrome, COPD-obstructive sleep apnea syndrome, pulmonary embolism, gastro-oesophageal reflux, anxiety-depression, pulmonary hypertension. Exposure to triggering factors, viral infections, treatment insufficiency may cause asthma exacerbations. Smoking cessations, prevention of infections, long-acting anticholinergics, long-acting beta 2 agonists, inhaled corticosteroids, phosphodiesterase-4 inhibitors, mucolytics, prophilactic antibiotics can be effective on the prevention of COPD exacerbations. Asthma exacerbations may be decreased by the avoidance of allergens, viral infections, occupational exposures, airpollution, treatment of comorbid diseases. Effective treatment of asthma is required to prevent asthma exacerbations. Inhaled steroids and combined treatments are the most effective preventive therapy for exacerbations. Patient education and cooperation is an element of the preventive measures for asthma attacks. Compliance to therapy, inhalation techniques, written asthma plans are required. The essential of COPD and asthma exacerbation treatment is bronchodilator therapy. Steroids are also implemented to the therapy, targeting the inflammation. Specific treatments of the cause (infection, airpollution, pulmonary embolism etc.) should be administered.