what3words is a universal location reference system based on a global grid of 57 trillion 3x3m squares. Each square has a pre-allocated, fixed, and unique 3 word address. 3 word addresses complement existing street addresses by providing an added level of specificity. In cities that don't have street addressing or parts of cities that are unaddressed, such as parks and open spaces, what3words provide a simple way to talk about location. Being able to clearly communicate location is essential to building a resilient city. The system is available to members of 100RC’s network, and can be used to help member cities more easily locate and communicate with their citizens.