The inflammation of the mucous membrane which lines the sinuses is referred to as sinusitis. It is also known as a sinus infection. The most common symptoms of sinusitis include a plugged nose, facial pain and thick nasal mucous. It may also exhibit other symptoms such as fever, headache, sore throat, cough and poor sense of smell. It is caused due to infections in the respiratory tract, allergies and air pollution. It can also be caused due to structural problems in the nose. People suffering from respiratory diseases like asthma, cystic fibrosis or having poor immune function tend to experience long term sinusitis. Bacterial and viral sinusitis are distinguished by watchful waiting in the initial period, however, a CT scan is used to diagnose chronic sinusitis. Pain killers such as naproxen, nasal steroids and nasal irrigation are used to minimize the effects of its symptoms. The treatment of sinusitis ranges from using antibiotics in acute disease, to surgery in people facing chronic sinusitis. This book contains some path-breaking studies on sinusitis. Those in search of information to further their knowledge will be greatly assisted by this book. This book will serve as a valuable source of reference for graduate and post graduate students.