Boundless San Francisco seeks large-scale proposals to improve the city and has $150 million to turn some into reality.

The first phase may select three to seven finalists. Each will receive between $1 million and $3.5 million to develop the idea before the final decision.

One to three projects will then receive grants of $10 million to $50 million. The competition accepts organisations from different sectors and countries, not architecture practices alone.

The first application closes on 11 September, with an information session planned for 18 August. Ambition, feasibility, outcomes and sustainability form part of the assessment.

AdvertisementARQUITHEAArchitecture for seeing more clearlyIdeas, buildings and tools for understanding the city through real questions.Follow @arquithea_

The format's value lies in paying for development before demanding a complete proposal. A complex urban idea needs partners, data and testing; pretending it can all be solved for free on one board impoverishes competition.

The question

What should a team test before applying?

Whether the proposal can measure outcomes, build a local coalition and use the funding without depending on an improbable regulatory change. The size of the prize also increases the duty to prove delivery.