We at Fab Lab Barcelona aim at fostering transitions to Sustainable & Productive cities by empowering citizens, organizations, and institutions to rethink how we live, work, and produce. Through innovation in digital fabrication, circular economy practices, and community-driven research, we explore and prototype solutions that reduce environmental impact while increasing local resilience and productivity. By connecting global knowledge with local action, we strive to build urban environments that are more equitable, regenerative, and adaptable to future challenges.