City Observatory is a daily source of data analysis and policy recommendations on how to make cities successful. The site helps readers separate fact from fiction when it comes to cities. This week, we talked with City Observatory founder and economist Joe Cortright.

Detroit was once the innovation center of America. Ingenuity propelled a booming auto industry, Motown synthesized and popularized a new form of music, and social change poured out on race and workers’ rights. In his new book, “Once in a Great City,” David Maraniss has captured this story of Detroit of the early ’60s. Born in Detroit, David is an associate editor at The Washington Post and a Pulitzer Prize-winning journalist and bestselling author.

The Center for Active Design has led the development of design guidelines for promoting physical activity.

While between projects in late 2007 and early 2008, Marcus Westbury, a maker, festival director and writer, was exploring his hometown of Newcastle, Australia, and found dozens of buildings and once-vibrant streets that 'had fallen into disrepair and despair.' Today, however, Lonely Planet describes Newcastle as a city whose 'time has finally come.' Marcus' new book, 'Creating Cities,' tells the story of how Newcastle transformed.

Erin Kelly is program manager of Innovative Landscapes, an initiative of Detroit Future City.

Make your way to the edge of downtown Detroit, and you will find a river. Until recently, it wouldn't have been a very inviting experience. But today, the Detroit riverfront has become one of America's best waterfront parks. Mark Wallace is president and CEO of the Detroit Riverfront Conservancy, the organization responsible for turning the waterfront into a great place for people.

Attracting and retaining talent is at the top of the economic development agenda in many U.S. cities. And the organization that probably knows best how to do that is Campus Philly. Deborah Diamond is president of Campus Philly, and she joined us this week to talk about what the organization has learned.

Who doesn't love a great market? And there is none livelier than Reading Terminal Market in Center City Philadelphia. Anuj Gupta is the market's new general manager, and I talked to him about what makes the market so special.

Until last summer, Philadelphia’s Spruce Street Harbor was moribund, lacking people and energy. That is, until David Fierabend and his colleagues at Groundswell Design transformed it with inexpensive, temporary design changes that have made it the place to go in the city. He discusses the project and how it was done with Knight Foundation Vice President of Community and National Initiatives Carol Coletta.

Meg Daly is founder and president of Friends of The Underline.