Oral squamous cell carcinoma is one of the leading cancers of the oral cavity that involves a complex pathogenesis. Epithelial Mesenchymal Transition (EMT) is suggested to play a significant role during cancer progression and metastasis. EMT markers are used in oral cancer to identify tumor invasion and metastasis. This book emphasizes the various mechanisms of EMT along with various molecules involved in EMT and aims to facilitate the readers to acquire a sound knowledge on the process of EMT.