Made at Guildhall, London, on 29 June 2026, and offered to all who shape the world’s cities.
The built environment is the world’s largest industry, and one of its least recognised. It is a $380 trillion asset class. It sustains a quarter of a billion jobs. It accounts for a third of all global energy use and carbon emissions. It produces some $13 trillion of construction output every year.[1] It is also the world’s single largest investment opportunity. No other sector comes close in scale, permanence, or consequence.
Yet it has long operated as a collection of disciplines, asset classes, and professional silos rather than as the unified force it is, and it has lacked a clear collective voice and a shared agenda.
The Built World Declaration is offered to everyone who plans, designs, finances, builds, operates and governs the world’s cities, and invites them to make its commitments their own. It looks forward by design. It sets out not what the sector has achieved but what it now intends to do, and it asks every professional and every organisation in the built world to support it and to act on it in their own work and in their own places.
The long expansion that has shaped cities for a century is giving way to a new era defined less by growth than by reinvention. In many places the task is no longer to build more but to adapt, retrofit, and renew what already exists. Where new cities and districts must still be built, they should be more frugal, more flexible, and more resilient than their twentieth-century predecessors. Meeting this will require long-term capital, patient stewardship, and coordinated leadership.
We therefore commit ourselves, our organisations, and our profession to five shared imperatives:
Adaptation – We will prioritise the reuse, retrofit, and renewal of what we have inherited, treating the existing city as an asset to be stewarded rather than a constraint to be replaced.
Resilience – We will design, finance, and operate cities to withstand climate, economic, and social shocks, and to recover and improve in their wake.
Flexibility – We will plan and build for change, creating places and assets that can adapt to uses, technologies, and needs we cannot yet foresee.
Frugality – We will use land, materials, energy, and capital with discipline, delivering more value and better outcomes from fewer resources.
Leadership – We will provide the long-term, cross-sector leadership and learning needed to align capital, climate, and collective prosperity, and to shape better cities and better outcomes for those who follow.
Turning these commitments into meaningful change requires practical action at city level. What this looks like is already visible in London. The New London Agenda, London’s framework for best practice in city-making, translates these same principles into a shared programme for its built environment community as it enters a new development cycle. It is offered here as an example of how a global agenda can be made specific, owned, and acted on in any city by the people who shape it.[2]
The Built World Declaration is offered in support of the wider global effort to make urbanisation work. In July 2026, ten years after the New Urban Agenda was adopted in Quito, the United Nations convenes the midterm review of its implementation, and member states will renew their commitments to sustainable urbanisation through to 2036.[3]
This is the contribution of our professions to that moment. Governments set the framework, but it is the people who finance, design, build, and operate cities who turn commitments into outcomes. We intend to be accountable for our part.
We undertake to act on these commitments, to measure our progress against them, and to return to them in the years ahead as a shared standard against which our leadership can be judged.
[1] Savills, Total Value of Global Real Estate (London: Savills Research, 2024); Oxford Economics, Global Construction Futures (Oxford: Oxford Economics, 2023); International Labour Organization, Statistics on Construction and Real Estate (Geneva: ILO, 2023); McKinsey Global Institute, The Net-Zero Transition: What It Would Cost, What It Could Bring (New York: McKinsey, 2022).
[2] NLA, The New London Agenda (London: NLA, 2024).
[3] United Nations, New Urban Agenda (Quito: United Nations, 2016); United Nations General Assembly, High-Level Meeting on the Midterm Review of the New Urban Agenda, New York, 16 to 17 July 2026.