The quantitative light-induced fluorescence (QLF) method is based on the natural fluorescence of teeth. Currently, the method is predominantly used in vitro and in clinical studies for early detection of carious lesions and for monitoring of de- and remineralization of white spots by quantifying the mineral loss and the size of smooth surface lesions. The objective of this paper was to demonstrate the potential of QLF for application in routine dental care. Experience with QLF was reported by selected cases, which enlightened the advantages of the method for caries detection and for evaluation of preventive interventions in caries-prone patients in daily practice.