White lesions of the oral cavity are commonly encountered in routine clinical dental practice. Many systemic disease conditions appear initially in the oral cavity. White lesions in the oral cavity may be benign, premalignant or malignant. Detection and early identification of these lesions is extremely important as it can facilitate prompt diagnosis and management which can eventually help in minimizing disease progression. The purpose of this book is to describe the detailed clinical and histopathological patterns of the white lesions affecting oral mucosa ranging from the genetically determined lesions to those that are neoplastic in nature along with the associated predisposing factors.