Previous studies, tools, implementation approaches as well as positive effects from the social, economic and technical point of view, aimed at developing CLABEL, a free software for the creation of on time access public catalogs, are exposed. WXIS and PHP were used for the design as a database management system and MARC 21 as a format for information interchange. The distribution was carried out according to the criteria established by Free Software Foundation for genera public licenses. Those features made CLABEL a very interesting system for the national and international library community.