The War on Drugs is a decades-long United States policy intended to curb illegal drug use and trafficking. Long story short: it has not worked to reduce drug use or trade, and the policy has had devastating effects, especially on...

How does a city become known as a "music city"? Publicist Elizabeth Cawein explains how thriving music scenes make cities healthier and happier and shares ideas for bolstering your local music scene -- and showing off your city's talent...

Jaime Lerner reinvented urban space in his native Curitiba, Brazil. Along the way, he changed the way city planners worldwide see what's possible in the metropolitan landscape.

Robin Chase founded Zipcar, the world’s biggest car-sharing business. That was one of her smaller ideas. Here she travels much farther, contemplating road-pricing schemes that will shake up our driving habits and a mesh network vast as...

Microsoft's Stephen Lawler gives a whirlwind tour of Virtual Earth, moving up, down and through its hyper-real cityscapes with dazzlingly fluidity, a remarkable feat that requires staggering amounts of data to bring into focus.

Why build a virtual world? Philip Rosedale talks about the virtual society he founded, Second Life, and its underpinnings in human creativity. It's a place so different that anything could happen.

New York was planning to tear down the High Line, an abandoned elevated railroad in Manhattan, when Robert Hammond and a few friends suggested: Why not make it a park? He shares how it happened in this tale of local cultural activism.

How do you build a product people really want? Allow consumers to be a part of the process. "empathy for what your customers want is probably the biggest leading indicator of business success," says designer Tom Hulme. In this short...

With his team at SENSEable City Lab, MIT's Carlo Ratti makes cool things by sensing the data we create. He pulls from passive data sets -- like the calls we make, the garbage we throw away -- to create surprising visualizations of city...

In this emotionally charged conversation with journalist Kurt Andersen, designer David Rockwell discusses the process of building a viewing platform at Ground Zero shortly after 9/11.

Call it "fuel without fossils": Jonathan Trent is working on a plan to grow new biofuel by farming micro-algae in floating offshore pods that eat wastewater from cities. Hear his team's bold vision for Project OMEGA (Offshore Membrane...

The prevailing image of where refugees live is of temporary camps in isolated areas -- but in reality, nearly 60 percent of them worldwide end up in urban areas. TED Fellow Robert Hakiza takes us inside the lives of urban refugees -- and...

How To Avoid the Next Atlantis

Author Steven Johnson takes us on a 10-minute tour of The Ghost Map, his book about a cholera outbreak in 1854 London and the impact it had on science, cities and modern society.

Outside.in's Steven Johnson says the Web is like a city: built by many people, completely controlled by no one, intricately interconnected and yet functioning as many independent parts. While disaster strikes in one place, elsewhere,...

Every city has its neighborhoods, cliques and clubs, the hidden lines that join and divide people in the same town. What can we learn about cities by looking at what people share online? Starting with his own home town of Baltimore, Dave...

Bees have been rapidly and mysteriously disappearing from rural areas, with grave implications for agriculture. But bees seem to flourish in urban environments -- and cities need their help, too. Noah Wilson-Rich suggests that urban...

If you want to go out and start your own cemetery in the uK, says Alison Killing, "you kind of can." She thinks a lot about where we die and are buried -- and in this talk, the architect and TED Fellow offers an eye-opening economic and...

It's an unfortunate reality in nearly every major city—road congestion, especially during rush hours. Jonas Eliasson reveals how subtly nudging just a small percentage of drivers to stay off major roads can make traffic jams a thing of...

Adults tend to think of kids as "future citizens" -- their ideas and opinions will matter someday, just not today. But kids make up a quarter of the population, so shouldn't they have a say in what the world they'll inherit will look...

Looking back over his long career, architect Moshe Safdie delves into four of his design projects and explains how he labored to make each one truly unique for its site and its users.

Far too many Americans are illiterate in power — what it is, how it operates and why some people have it. As a result, those few who do understand power wield disproportionate influence over everyone else. "We need to make civics sexy...

Humans take up a lot of space, but engineers are already coming up with some amazing solutions for the future.

What's that awful smell? Cat urine? Semen? Rancid butter? Possibly one of these gorgeous city trees?