Monofluorophosphate (MFP) dentifrices have been tested extensively in clinical trials in the last 2 decades. This paper reviews findings in these studies. The average benefit seems to be about 25% and has not changed with time. The benefit is the same in fluoridated and nonfluoridated areas. MFP is compatible with calcium-containing abrasives and calcium ion. There is a possibility that use of calcium-containing MFP dentifrices of optimal formulation may be particularly beneficial. There seems to be a relationship between F concentration and benefit derived. Supervised and unsupervised use of MFP dentifrices results in comparable benefits. The relative efficacy of NaF and MFP dentifrices is not known. It may be advantageous to combine MFP and NaF in one dentifrice formulation or to combine use of MFP dentifrice with a NaF rinse.