This book contains articles on the land snail family Clausiliidae and lists of its valid taxa, parts of which have already been published in the last decades. The respective articles either give general information on the family or deal with special biological and palaeontological aspects, which are especially interesting, such as evolution and development of the closing apparatus, subspecies evolution and hybridization, mating biology and fossil record and its changes in the Tertiary and Quaternary. In other chapters problems in systematics and phylogeny of certain clausiliid groups are discussed. A chapter on practical work with Clausiliidae is also included. Coloured illustrations of the shells of representative species of all clausiliid groups give a survey of the diversity of the group and can serve as a basis for determination. In addition to this, the book contains the description of new tribes and new genus and species taxa.