The call for applications for city-to-city exchanges is now open and provides support to urban authorities in addressing implementation challenges related to sustainable urban development. The purpose of an exchange between cities under the European Urban Initiative is to improve the applicant's ability to address the identified challenge through a process of mutual learning. If selected, applicants will have the opportunity to gain practical knowledge and know-how tailored to their identified challenge through personal visits to the partner city. The partner cities share new working methods and innovative approaches to specific implementation challenges.