Against the social trust crisis of our era, an acclaimed urbanist shows how we can design healthy relationships back into our communities, online spaces, and nations.

Imagine you dropped your wallet and a stranger found it. Would you get it back? Your answer to this question says a lot about you: It predicts your happiness, the health of your community, and even the stability of your country. Trust in other people is integral to the good life.

The bad news is that, as rates of alienation and polarization skyrocket, social trust has plummeted in the United States and other parts of the world, widening cracks in society and making us all more susceptible to loneliness, division, violence, and extremism.

In The Trust Experiments, Charles Montgomery reveals that this crisis isn't being driven by a sudden drop in trustworthiness. It's the result of a collision between human psychology and countless bad design decisions over the course of modern history: Contemporary homes discourage neighborly contact. Cities force us into solitary commutes. Social media algorithms widen schisms across society. And government policies deepen inequity, breaking trust between people and the institutions that serve us.

But the good news is that these broken systems can be transformed. Montgomery uses the science of trust to show us how. From the baugruppen of Germany to the urban villages of Vancouver to the Utopias of Mexico, Montgomery takes us into communities that have been designed to promote mutual aid. He meets Taiwanese activists who are using AI to foster empathy among strangers. He shows how governments from Denmark to Costa Rica have been redesigned to boost trust across entire societies. And he shows how we can all use design in our own lives to help rebuild the trusting relationships that keep us happy, healthy, and strong.