The document discusses how cities can share knowledge openly to become smarter. It proposes establishing an open data platform and shared standards to solve problems collaboratively across sectors. A three-part approach is outlined: 1) Conducting a maturity assessment to develop open data strategies; 2) Launching joint data pilots with partners from government, industry, academia and citizens; 3) Using a testbed infrastructure to test interoperable solutions. The goal is to reduce fragmentation, create a level playing field and link cities internationally by taking an open, collaborative approach driven by real challenges.