Dental caries is nearly universal--no nation is free of this disease. Although the ability to prevent dental caries is imperfect, scientifically evaluated protective measures are available. These can substantially decrease caries when implemented and sustained, yet a large portion of the world's population, especially children, is unaided or receives outdated or unproved measures. The best individual and community protection against dental decay today is offered by the proper use of fluorides. Community water fluoridation is the most effective, practical and least expensive method. Because community water fluoridation is unavailable to many, effective alternatives must be introduced. The majority of carious lesions in children during their school years occur on occlusal surfaces. Because this surface is least protected by fluorides, adhesive sealants should be used to augment the partial protection derived from fluorides. Sound health education and health promotion activities, validated by research, form the foundation upon which prevention is organized, implemented and perpetuated.