Giant cells are multinucleated cells that are seen in various physiological as well as pathological conditions. They are important mediators of tissue remodeling, repair and also for removal of foreign materials and various pathogens. The book includes information regarding mechanism of formation of giant cells, classification, morphology and its significance in the associated giant cell lesions. Also there is a detail description of clinical, radiographic, histopathology of various giant cell lesions of oral cavity along with their representative photomicrographs.