A major diagnostic application of low power lasers is the detection of caries, using fluorescence elicited from hydroxyapatite or from bacterial by-products. Laser fluorescence is an effective method for detecting and quantifying incipient occlusal and cervical carious lesions, and with further refinement could be used in the same manner for proximal lesions. Laser technology for caries removal, cavity preparation and soft tissue surgery is at a high state of refinement, having had several decades of development up to the present time. Lasers in current form are now able to remove tissue in bulk at a similar rate to conventional methods such as bur and turbine handpiece. Some lasers may, however, provide precision cutting, which may be developed further in the future. Alternative uses of laser light are potentially more beneficial in the shorter term. The use of diode lasers as a means of activating a photosensitizer to carry out photo-activated disinfection appears to be beneficial. Key words: Dentistry, LASERS