Leukoplakia of the oral mucosa is a potentially malignant disorder, which means that there is an elevated risk of transformation into a squamous cell carcinoma. The term oral leukoplakia is a clinical diagnosis for a predominantly white lesion which is not immediately recognizable as another well definable lesion which is white in appearance. Oral leukoplakia is generally an asymptomatic disorder of the mucosa with a prevalence of less than 2 per cent in the adult population. Tobacco usage is considered to be the most important etiological factor. Malignant transformation into a squamous cell carcinoma occurs in about 1 per cent per year. A patient with oral leukoplakia is generally referred to an oral and maxillofacial surgeon, who takes a biopsy for a definitive histopathological diagnosis. The outcome of the histopathological study, which may vary from hyperkeratosis to invasive squamous cell carcinoma, will determine the treatment. It is preferable that every leukoplakia is removed to reduce the risk of malignant transformation. Long term follow-up is indicated. Follow-up may in some cases be performed by the general dental practitioner.