This is the first (since 1952), original and fully colorful account of the entire fauna of terrestrial molluscs of most of the Palearctic. It covers 46 families, 225 genera and 781 species and subspecies. Information on each species-level taxon includes a reference to the original description, complete synonymy, data on the type locality and type material, size, distribution, and, when appropriate, taxonomic and nomenclatural notes. Virtually all of the species are illustrated in color, both the photos and drawings usually being based on the type material from various repositories. The photographs of most of the types are being published for the first time. This is an indispensible tool to anyone interested in land snails and slugs.