Cities across Europe and in the U.S. are finding that their problems and solutions are not all that different. From issues like housing to environmental sustainability, city officials are turning in increasing numbers to cross-sector collaboration as the foundation of innovation.

Shared Challenges, Shared Language

Whether you are in Paris, France, or Los Angeles,USA, local government leaders are grappling with issues arising from a lack of cheap housing, the challenge of coping with effects of climate change, road safety, as well as issues of inequality. Such issues are not limited to individual nations but involve approaches beyond borders. Speaking at the POLIS Network Leadership Summit, leaders from both Europe and America emphasized that it was important for cities to cooperate not only with sectors such as the third sector and businesses but also with their governments.

The strength of this conversation has been the development of a common language. This shared vocabulary is not just rhetorical as it allows Paris to learn from Los Angeles on housing affordability, and Chicago to adapt Berlin’s climate strategies. Resilience, sustainability, and equity are now part of a standard vocabulary that has been adopted on both continents. While European cities talk about the Green Deal and a circular economy, American cities are talking about community empowerment and workforce development. Equally, however, are a set of common values that must involve a diversity of voices in a city, and contribute to a common understanding of how cities can gain the trust of their citizens.

The EU Cities Gateway Initiative

The EU Cities Gateway Initiative, which runs from 2025 to 2029, provides a critical platform for connecting European, U.S., and Canadian cities. This initiative promotes cooperation among clusters that relate to a circular economy, nature-based solutions, digital innovation, and sustainable housing. Cities that face the Atlantic side are linked in a manner that other cities are invited to learn from and join.

Within these clusters, cities are matched up across the Atlantic to co-create together. Toronto’s green building experience is being shared with innovations in Barcelona’s modular housing, while innovations in Tampere’s digital tools are generating new ideas in Atlanta. Equally, there is a focus on knowledge platforms and pilots, so that knowledge gained in a city can help other cities. The EU Cities Gateway represents far more than a sharing of best practices. Instead, it represents a means of developing a new form of “urban diplomacy.” Linking together mayors, NGOs, companies, and regional administrations, it deepens trans-Atlantic relations and provides a basis for a long-term partnership.

Case Study: Chicago’s Climate Infrastructure Partnership

In 2025, a Climate Infrastructure Partnership in Chicago initiated projects that involve cooperation between city hall, local organizations, and corporate sponsors to move projects related to resilience forward. The priority areas are green stormwater infrastructure, a transition to renewables, and workforce development in underserved communities.

The municipal government establishes policy parameters, adjusts zoning laws, and offers financing for scaling. Nonprofits, such as Elevate Energy, are involved in outreach, ensuring that low-income communities are served by this new infrastructure. The corporate sector, which would involve companies like engineering firms and those that specialize in renewable energy, contributes innovation, expertise, and finances.

This effort has already delivered tangible outcomes, including an increase in green roofs over public housing, solar installations in community centers, and the development of training programs for energy-related employment. This should be a model of how to manage environmental, economic, and equity agendas.

Lessons Learned

The cross-Atlantic dialogue raises a number of important issues. Collaboration requires as a consideration a focus on trust and transparency. Multi-stakeholder approaches, which involve all types of nonprofits, for-profits, and government, are very effective. Learning from other places in order to avoid reinventing the wheel can be very effective for a city. The Chicago partnership offers a successful model that can be replicated in other cities, and tests of circular economies, nature-based solutions, and other concepts in many European cities offer valuable insights into how a sustainable world can be created. 

Together, cities are “living laboratories of democracy and resilience, and cross-learning among them has been their greatest strength.” The bottom line: “Collaboration Without Borders.” European and American cities are sharing best practices, but their cooperation is also forging a common future. This has been true in “partnerships where nonprofit knowledge, entrepreneurial spirit, and public policy seek a common aim; building a resilient world.” The next decade will test whether cities can sustain these partnerships. If they do, collaboration without borders will not just be a slogan, it will be the foundation of a resilient world.