This whitepaper sets out a vision for a different path for AI. Societies don’t have to just consume the AI technologies shaping their lives—they can create them. We call for a new collective enterprise: building AI infrastructure for the common good. Public investments can unleash a wave of innovation, expanding access to better tools, and in time expanding our collective imagination. It highlights three features of Public AI that ensure it advances the common good: Public Access – Certain capabilities are so important for participation in public life that access to them should be universal. Public AI provides affordable access to these tools so that everyone can realize their potential. Public Accountability – Public AI earns trust by ensuring ultimate control of development rests with the public, giving everyone a chance to participate in shaping the future. Permanent Public Goods – Public AI is funded and operated in a way to maintain the public goods it produces permanently, enabling innovators to safely build on a firm foundation. It sets out a roadmap for public investments into public goods at each layer of the AI stack to lower the costs of innovation, vertically-integrated public utilities to fund sustainable development, and innovative new public goods that invent and scale breakthroughs.