Cancer of the oral cavity and oropharyngeal regions constitute about 30% of all cancers seen in India, with Trivandrum District in southern India having one of the highest incidence. Despite easy accessibility for examination and diagnosis, these tumours still cause high mortality, emphasizing the need for better methods of diagnosis and more importantly prognosis. Most oral carcinomas initially present as premalignant lesions and hence understanding their biology and behaviour is vital to the management and control of the disease. This review presents some of the clinico-pathological, immuno-pathological and immunological aspects of oral precancers.