This book is about oral cancer (oral squamous cell carcinoma). This disease is one of the top five killers in Pakistan. It is also a major killer in the neighbouring countries. The incidence rate of oral cavity cancer in Karachi is estimated to be among the highest in the world. Well known risk factors for oral cancer are smoking and alcohol while alternative chewing habits are implicated in sub continent. As many individuals are exposed to these risk factors, only a small proportion develops oral cancer. This suggests that other factors may also play a role in oral carcinogenesis. Recently, Human Papillomavirus (HPV) infection and p53 gene mutation has been shown to play a role in the development of oral cancer. This work is a collection of information gathered through personal research experiences and interaction with oral surgeons and pathologist, over a period of ten years. This book covers all the essential topics such as epidemiology, etiology, pathology, clinical presentation, diagnosis, and management of patients suffering from oral cancer. It is hoped that this work would be of some use to researchers, students as well as oral surgeons engaged in dealing with oral cancer.