The politic and legislative life of the Andalusian Autonomous Community’s Library System is 20 years old now. This paper details the development of the rules and regulations pertaining to the Andalusian Library System (SIBIA), both at regional and national level, from the beginning to the present. Five stages are clearly discernible offering a chronological overview of the past, present and future of public library services in the Andalusian Autonomous Community, that is, the “Andalusian Library Movement.” Mention is made of the latest legislation changing noticeably SIBIA’s organisational structure set by the Andalusian Library Law.