Circular fingerprints -- the representation of molecular structures by atom neighborhoods -- have been applied to a wide range of applications, such as similarity searching and the prediction of absorption, distribution, metabolism, excretion and toxicity properties. In recent years there has been a surge in applications resulting from the superior performance of circular fingerprints in comparative studies. This feature examines the nature of circular fingerprints as well as their applications, including virtual screening, metabolism prediction and the estimation of pK((a)) constants.