The mode of life of leaf beetles (Chrysomelidae) might appear less interesting, as compared to free and fast roaming and hunting ground beetles (Carabidae), eusocial bees (Apidae), or so many other behaviourally fascinating insects. Chrysomelids generally hatch from eggs, which are typically laid onto their food plants. Larvae eat, moult, and pupate on or very close to these plants. Following emergence as adults reproduction often proceeds without complex courting and, in most cases, without eating much or moving for longer distances. All of this is quite insect-like and seemingly pedestrian. Nevertheless, the mechanisms of host plant selection, the wide range of defensive devices, the multifariousness of shapes and the gaudiness of colours of their body ? to name just a few phenomena of their biology ? continuously fascinate quite a number of scientists, let aside many other beetle enthusiasts. Every four years, in connection with the International Congresses of Entomology, an informal group of leaf beetle workers meets for an International Symposium on the Chrysomelidae. Last time, we met on August 23, 2012, in Daegu, South Korea for the 24th International Congress of Entomology. Of the seven papers therein presented, four are, in extended and elaborated versions, published in the present volume. Three more papers on Chrysomelidae have been submitted independently and are included here as well. The present volume 4 of the series Research on Chrysomelidae is the second published as a special issue of ZooKeys. Publishing with Pensoft?s ZooKeys is not only fast and affordable, but also allows the inclusion of colour illustrations ad libitum, in both the printed and digital versions, so that the authors can easily share their excitement on their scientific objects with their readers. We, the editors, are glad to present this volume and hope that it will be valued not only for its scientific value but also attract the attention of non-chrysomelidologists to the fascinating world of leaf beetles. Hopefully, many such volumes will follow, so that our series will develop into an attractive forum for sharing news about a scientifically interesting, economically important, and emotionally rewarding group of insects.