How would you define a successful city in modern context? originally appeared on Quora, the place to gain and share knowledge, empowering people to learn from others and better understand the world. You can follow Quora on Twitter, Facebook, and Google Plus.

In a successful city everyone participates and is able to realize their dreams. In my book, The Rise of the Creative Class, I set out a simple formula for a successful city I called the 3Ts: talent, technology, and tolerance. Successful cities both develop talent and are a technology leader. But neither of these, alone or working in tandem, are sufficient; both technology (companies) and talent (people) can move away as I saw firsthand when I lived in Pittsburgh. A successful city must also be open to all kinds of people - men and women, ethnic and racial minorities, locals and immigrants, married and single, gay and straight. Importantly, all three Ts must be working together. Each alone is necessary, but insufficient in generating regional development.

In addition, a great city must also recognize, enhance and invest in its quality of place. Borrowing a French word used in categorizing wines, we can call this the fourth T, Terroir. Great cities must showcase their authentic assets, culture, neighborhoods, and natural amenities that make them unique and special.

The central argument of my latest book, The New Urban Crisis, is that the clustering of innovation and creativity and knowledge is two-sided. On the one side, the clustering of urban activity drives innovation, drives economic growth, and is the main source of productivity. But on the other side, it also creates the divides in our society. A successful modern city balances these two forces. It’s no longer enough to just push on the lever of urbanization and city growth. It’s really important now to begin to make that growth more inclusive so that everyone can partake in the opportunity and realize their dreams.

This question originally appeared on Quora. More questions on Quora:

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