This paper reviews some common methods for the assessment of caries risk. It also describes a new way of illustrating the caries risk profile of an individual, the Cariogram. Past caries experience and socioeconomic factors are often used for prediction of caries. As prediction models, the methods are simple, inexpensive and fast. However, they are not risk models, as they do not specify which particular risk factors are operating. Various biological factors can be used for risk assessment. Common ones are bacteria, diet and host factors. Taken separately, these biological factors often have limited predictive values. Socioeconomic factors often have a heavy impact on the biological factors as they can explain why an individual, for example, has a cariogenic diet or neglects oral hygiene. The biological factors are the immediate cause of the cavities. Caries experience is an illustration of how the host copes up with the biological activity. To facilitate the interpretation of biological data, the Cariogram was developed. It is a computer program showing a graphical picture that illustrates a possible overall caries risk scenario. The program contains an algorithm that presents a 'weighted' analysis of the input data, mainly biological factors. It expresses as to what extent different etiological factors of caries affect caries risk. The Cariogram identifies the caries risk factors for the individual and provides examples of preventive and treatment strategies to the clinician.