The population of today is better educated regarding the malignant potential of pigmented lesions and this awareness may lead many to see a dermatologist for evaluating skin lesions and likewise, patient may notice an area of increased pigment in the oral cavity and seek evaluation from dentist. This book delineated the factors that will help the clinician differentially diagnose pigmented lesions of oral cavity and the following conclusion can be drawn: ¿The differential diagnosis of oral pigmentations can be lengthy, particularly when the pigmentation is macular & diffuse or multifocal. ¿Diagnosis made on clinical grounds alone, remains "provisional." ¿Biopsy is the helpful aid to diagnosis for localized lesions, the more diffuse lesions will require a thorough history & laboratory studies in order to arrive at a definitive diagnosis. ¿Occasionally, immunohistochemical stains such as melanocyte marker HMB-45 and macrophage marker CD68 may be required to arrive at a correct diagnosis.