Oral squamous cell carcinoma is the third most common cancer in Indian subcontinent affecting people with lower socioeconomic status. As early stage oral squamous cell carcinoma patients can be treated with single modality treatment, multimodality regimen is adopted for high risk advanced stage cancers with multiple adverse features like extra nodal extension, lymphovascular invasion and perineural spread. This book outlines the principles of adjunctive therapy in oral cancer patients with special reference to different techniques, indications of radiotherapy and role of chemotherapeutic regimes in improving the overall survival of advanced stage oral cancer patients.