The term minimal intervention is relatively new in dentistry and has been introduced to suggest to the profession that it is time for change in the principles of operative dentistry. The disease should be treated first; the surgical approach should be undertaken only as a last resort and then with the removal of as little natural tooth structure as possible. This article discusses the advances in techniques and materials that have led to change and attempts to put them into perspective. Treatment should begin with identification and elimination of the disease. There will then be a need for limited restoration of actual cavitation arising from demineralization of the tooth crown. Restorations, per se, will not prevent or eliminate disease. Caries is a bacterial infection and, until the microflora is controlled, all restorations are at risk of further demineralization in remaining tooth structure. This leads to the continuum of replacement dentistry that keeps the profession occupied for much of its productive time. If this cycle is to be broken, the profession must first acknowledge the primacy of prevention.