Cough is a common physiological reflex that functions as a protective mechanism to clear the airways of irritants, mucus, or foreign particles. It is typically classified by duration into acute, subacute, or chronic categories and may be associated with a broad spectrum of underlying causes, including infections (e.g., common cold, influenza), respiratory conditions (e.g., asthma, chronic obstructive pulmonary disease), and environmental exposures (e.g., smoke, allergens). While often a benign response to airway irritation, persistent or severe coughing can signal a more serious underlying disorder. Evaluation of chronic cough requires a thorough clinical approach, incorporating patient history, physical examination, and diagnostic investigations such as imaging and pulmonary function tests. Management strategies are guided by the identified etiology. This chapter underscores the clinical importance of cough both as a symptom and a diagnostic clue, highlighting the necessity of careful assessment to uncover its root cause and guide appropriate treatment.