Spontaneous pneumothoraces occur in individuals who have not experienced antecedent thoracic trauma. Primary spontaneous pneumothorax occurs in otherwise healthy individuals with no clinically apparent lung disease, whereas secondary pneumothorax is a consequence of an underlying lung disease. This review focuses on their management in the acute medical setting. The specific issues of simple aspiration versus intercostal tube drainage, who can be discharged home safely, and when to refer to a respiratory physician are addressed. In addition, recent developments in the management of pneumothorax are presented.