With a CO2 laser superficial lesions of the oral mucosa can be removed by evaporation. During CO2 laser evaporation there is minimal damage to the surrounding tissue, resulting in minimal scarring after healing. Therefore the CO2 laser seems to be a modality which is appropriate for the treatment of leukoplakia of the oral mucosa. In 1985, the effect of CO2 laser light on mucosa and the healing after CO2 laser evaporation was studied. In addition, clinical research was carried out concerning the effectiveness of CO2 laser evaporation in the treatment of 103 cases of leukoplakia of the oral mucosa The cure-rate was 91% and no malignant degenerations were seen in the treated area. The group was expanded (282) and evaluated again, with a cure-rate of 90%. In 1% of the cases, malignant degenerations were seen. CO2 laser evaporation seems the modality of choice for the treatment of leukoplakia of the oral mucosa.