Constipation is one of the most common disease in Western countries. Its prevalence is widely variable (5-30%), depending on criteria utilized for diagnosis. Usually constipated patients have mild-moderate symptoms and are self-treated. Only patients that do not benefit from simple therapy (dietary supplementation of fiber and water, laxatives) need examinations such as blood tests, colonoscopy, radiography with bario-enemas, intestinal transit time and manometry. These tests are able to differentiate idiopathic from secondary constipation. Idiopathic chronic constipation is a collective term that involves different functional disorders. More specific investigations (oro-cecal transit time, manometry, electromyography) allow one to distinguish between two different patterns of idiopathic chronic constipation (slow transit constipation and pelvic floor disease) and to utilize the appropriate treatment of disease. The aims of this paper are to review the recent world literature on chronic constipation and to propose a diagnostic and a therapeutic flow chart for this disorder.