Citilab in Cornella de Llobregat, Spain is a case study of an open living lab located in a small-to-medium sized city. Citilab addresses five key problems in developing as a living lab: engaging local community members as innovation partners, starting an innovation program relevant to local needs, balancing innovation and learning, managing collaboration between different stakeholder groups, and developing a sustainable funding model. By taking a bottom-up, user-driven approach focused on local issues, Citilab has built a community of over 4,500 members working on projects in areas like senior services, education, arts, and museums.