This is the first of a series of several books that are planned to be published about all marine gastropods that live in the Croatian part of the Adriatic. In this first part, 170 species from the subclasses Patellogastropoda, Vetigastropoda, Neritimorpha and Caenogastropoda are presented. The book has 496 pages and consists of a photographic part containing 304 colour plates, and a textual part with a list of all taxa and their description in Croatian and English. 1.601 specimens are illustrated with a total of 3.644 photographs of shells and live individuals.