WHO data suggest that all over the world the prevalence of caries has declined at the end of the previous and in the first decade of the present century. This decline started wherever the use of effective fluoride toothpaste became commonplace. Even though the decline is considerable with a 90 % reduction in DMFT for 12-year-olds in Western Europe and the USA, caries still affects 60–90 % of the children throughout the world. In the high- and middle-income countries, the nature of caries has changed from a rapid progressing disease of childhood to a slowly progressing disease throughout adulthood and even old age. However, throughout the world, the circumstances for caries differ, e.g., low-income countries experience more caries with higher sugar consumption, while between high-income countries this correlation is reversed. In high-income countries, fluoride is widely used and preventive programs in dental offices are in place. These programs, if effective, may not be a realistic option in low-income countries. In order to reduce caries in the world even further, the use of effective and affordable fluoride toothpaste should be encouraged and enabled.