The LibrarIN project, coordinated by Athens Technology Center (ATC), has released its third policy brief: Collaborative Innovation and Best Practice Diffusion in European Libraries: Adapting for Local Impact. Authored by a team of experts from Rete delle Reti, The Lisbon Council, the National Library of Latvia, the Austrian Institute of Technology and Athens Technology Center, this brief explores how European libraries can effectively share, adapt, and scale innovation to meet local needs. The brief is a joint effort between the LibrarIN project and the Erasmus+ TELL project for transparent European learning libraries.