Chronic rhinosinusitis is characterized by nasal purulence accompanied by malaise, postnasal drip and nasal dryness or crusting. It is a condition that is very difficult to treat and can be very disabling to the patients. A clinical diagnosis is based on history and evaluation with endoscopy, and computerized tomographic scanning. The etiology of chronic rhinosinusitis is multifactorial and comprises a vicious cycle of pathophysiological, anatomical, and constitutive factors. Predisposing factors include ciliary impairment, allergy, nasal polyposis, and immune deficiency. Treatment is aimed at reducing mucosal inflammation and swelling, controlling infection, and restoring aeration of the nasal and sinus mucosa. The choice of treatment is influenced by many factors including past medication, duration of symptoms and the presence of allergy/nasal polyps. Pharmacologic treatment, with local or systemic corticosteroids such as mometasone furoate, fluticasone propionate, beclometasone dipropionate or oral prednisolone coupled with nasal lavage with isotonic saline solutions are the cornerstones of disease management. Systemic antibiotics including amoxicillin/clavulanic acid, ciprofloxacin, clarithromycin, and trimethoprim/sulfamethoxazole (cotrimoxazole) are often administered to patients with chronic sinusitis and underlying bacterial infection. In patients with underlying allergy, additional treatment with antihistamines should be considered. Aeration of the sinuses may temporarily be improved with local nasal decongestants such as oxymetazoline. If symptoms persist after aggressive medical treatment, surgery should be considered. Surgery should be functional and involve widening the natural drainage openings of the sinuses and preserving the ciliated epithelium as much as possible. In the case of nasal polyposis surgery is more aggressive involving removal of the diseased polypous mucosa. It is recommended that medical treatment should be continued post sinus surgery.