If the start-up space is one big chess game, then 26-year-old Joshua Kushner is already a grand master. "There's opportunity everywhere," Kushner says. "You just have to understand the nature of all the moving pieces." Four years ago, while an undergraduate at Harvard, Kushner cofounded the social-gaming platform Vostu out of his dorm room; now it's the largest company of its kind in Latin America, with 35 million registered users and close to 600 employees. Having proven himself as an entrepreneur, Kushner—the youngest member of the wealthy clan that also includes his father, Charles, a New Jersey real-estate magnate, and his brother, Jared, the owner of the New York Observer and (Donald Trump's son-in-law)—turned his sights in 2009 to venture capitalism, founding the angel fund Thrive Capital. The company has since invested in nearly 25 start-ups, including the group-messaging service GroupMe, the online art emporium Art.sy, and the crowd-funding platform Kickstarter. Kushner also recently attended Harvard Business School. Why? Because despite his rapid rise, he wanted to prepare himself for the road ahead. "We're beginning to see what the Internet can do for our lives," he says, "but it's only the first inning." Here, Kushner weighs in on power breakfasts, how to pick the best start-ups, and where he goes for advice.

Details: What makes a start-up a success?
Joshua Kushner: I'm a big believer in entrepreneurs who are trying to either create or disrupt markets. For example, Art.sy—a company that I am actively involved in—is bringing art online, enabling consumers to view and purchase works outside of physical galleries. I believe that it has the potential to disrupt the art market in a very positive way.

Details: Beyond the initial funding stage, how do you help these businesses grow?
Joshua Kushner: I try to be actively involved in helping entrepreneurs think creatively about challenges and about how they can build their businesses in the most impactful way. Like with Art.sy, Carter [Cleveland] is the CEO, and as lead investor and vice-chair of the company, I try to be helpful behind the scenes.

Details: You led quite a group of investors with art.sy, including Eric Scmidt, Jack Dorsey, Wendi Deng Murdoch, and Dasha Zhukova. How do you move between established players and the new generation of entrepreneurs?
Joshua Kushner: It's seamless. I'm the kind of person who enjoys learning from everyone. I enjoy getting the perspective of someone my age, but some of my closest friends are in their seventies. These are guys who've built huge businesses, and they can help me think more creatively about my roles.

Details: Vostu's success suggests that you have a knack for predicting macro trends. What else is coming down the pike?
Joshua Kushner: Given that many new distribution platforms have emerged, I'm looking for products that can package content in a thoughtful, effective way. I am also fascinated with commerce and consumption online. The other big thing is commerce. In a two-year period Vostu went from 1 million users to capturing 30 percent of the Internet population of one of the fastest-growing-GDP Internet economies in the world. In this environment, capital-efficient businesses can reach unbelievable scale pretty quickly.

Details: Power breakfasts are popular in the New York start-up world. Do you have a favorite spot?
Joshua Kushner: I go to Maialino in Gramercy every morning. Many tech and media people go to Coffee Shop or Balthazar, but I prefer to have breakfast by myself or with one other person. It isn't about being secretive—I just love what I do and prefer to focus on my work.

Details: Ashton Kutcher sings your praises. How'd you meet?
Joshua Kushner: Through my brother Jared. I think Ashton is one of the smartest people in this space, and I really like working with him. We invest in a lot of the same companies, and I ask him for feedback on projects all of the time.

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