International legal and political mandates such as the Sustainable Development Goals and the Paris Agreement increasingly emphasize and embrace the role of local governments and city networks in achieving global sustainability goals, e.g in SDG 11 and the NAZCA (non-state actor zone for climate action) platform. The question of how to grow urban sustainability needs to consider highly varying local governance systems, regulatory settings, extend of the legal scope of action in unitary and federal states, local budgets and the power to raise taxes, potential postcolonial power structures, and the degree of legal pluralism present. Across a range of case studies encompassing cities all around the world, commonalities manifest in challenges and opportunities of strategic urban sustainability planning (e. g. development and climate action plans), the role of participation in effectiveness of design and implementation, and the urban power to influence greenhouse gas emissions. The findings support the path to action by raising awareness for the regulatory preconditions, clustering local governance systems, collecting and discussing governance systems, and exemplifying the significance of participation.