Premalignant lesions of the oral cavity are conditions of the epithelial part of the oral mucosal lining that carry an increased risk for the development of oral squamous cell carcinoma (OSCC) in that area. This group encompasses a mixture of lesions that are defined by clinical appearance, histology, or etiology (Table 1) (1). For some of these lesions, the premalignant character is doubtful as will be elaborated when discussing them. Moreover, it should be realized that lesions may not only be premalignant in the sense defined above but could also be risk factors, indicating an increased risk for developing OSCC anywhere in the upper aerodigestive tract (2,3). Moreover, other lesions could indicate an increased risk for the development of OSCC without being premalignant themselves.