This volume honours an outstanding Japanese carcinologist, Masatsune Takeda (National Museum of Nature and Science, Tokyo, Japan), on the occasion of his 70th birthday. Since 1967, Takeda-sensei (“sensei” is an honourific term for teacher or senior scientist in Japan) has devoted his life to studying the taxonomy of Brachyura and has published 323 papers over a long and illustrious career, and in the process, described 231 new taxa. In this volume, a total of 24 papers have been put together by 40 of his friends and colleagues to honour him. These papers cover a wide diversity of topics on the taxonomy, larval biology, palaeontology and ecology of Brachyura, Caridea, Stenopodidea, Astacidea, Axiidea, Anomura, Amphipoda, Isopoda and Mysida, all groups that Takeda-sensei loved.