It is nearly one hundred years since G. V. Black proposed a simple, five-stage classification for carious lesions based upon the site of the lesion and the type of restorative material likely to be used for restoration. In the absence of both effective preventive measures and a knowledge of remineralization his approach was essentially surgical: having identified a lesion remove it surgically, as well as all surrounding susceptible tooth structure, to prevent recurrence. Surgery is no longer regarded as the primary choice for treatment of a disease and there are many factors which suggest that this system is out of date. Preservation of natural tooth structure should be the principal aim and this is best achieved through remineralization. Remaining cavitated areas can then be restored more conservatively, thus assisting in maintaining aesthetics as well as strength in the tooth crown. If the profession is to adopt a new approach to operative dentistry it is suggested that the psychology of introducing a new classification for carious lesions is a desirable move.