The scientific community has rediscovered anuran larvae (tadpoles) as valuable subjects for developmental, evolutionary, ecological, ecomorphological and toxicological research. Innovative molecular methods have provided new insights. Field research combined with molecular genetics has vastly expanded our knowledge of species diversity and of environmental adaptations and has resulted in a revision of concepts. Correspondingly, molecular methods have broadly extended our understanding of amphibian development, leading to both new insights into evolutionary processes as well as support of medical research. The present work boldly attempts to update current knowledge on the larval biology of anurans more than twenty years after the highly commendable Tadpoles: The Biology of Anuran Larvae by Altig & McDiarmid (1999).