Summary: Asthma and chronic obstructive pulmonary disease (COPD) are the two most frequent chronic diseases of the respiratory tract in the population of patients followed by general practitioners (GP). Early diagnosis and the introduction of appropriate treatment is vital for the improvement of symptoms, decreased risk of exacerbations and improvement of patients’ quality of life. Diagnosis of asthma is based on typical clinical symptoms (dyspnea, cough, chest tightness and wheezing) followed by reversible and variable airflow limitation found in lung function measurements. In COPD, typical symptoms (chronic, productive cough and dyspnea) are associated with exposure to tobacco smoke or other harmful stimuli. Irreversible airflow limitation needs to be clearly proved before the final diagnosis is made. Differential diagnosis, additional tests and basic information regarding management of asthma and COPD are further discussed in the paper.