The frontal sinus has been recognized as a problem since Ambrose Pare first described a white sticky substance oozing from it during skull trephination in 1564. Although Lettre originally described frontal sinus trephine in 1704, Ogston reported the first external surgical procedure on the frontal sinus in 1884. Since then, there have been a myriad of frontal sinus procedures developed to deal with chronic frontal sinusitis. Over the last decade, functional endoscopic sinus surgery (FESS) has been accepted as the procedure of choice for the surgical management of chronic sinusitis. Because of the complex anatomy of the frontal recess, endoscopic intranasal approaches to this region continue to be an area of controversy. Of all the paranasal sinuses, endoscopic surgery of the frontal sinus is the most difficult and challenging. In this book titled 'Frontal Sinus Surgery: Predictive Factors of Surgical Outcome', patients with frontal sinus disease were studied at our hospital with respect to their clinical features, management, complications and follow-up. They were studied over a period of two years with an aim to identify factors that can help us predict the outcome of surgery.