SINGAPORE—What might a more economically open North Korea look like? For some Pyongyang elites, Singapore—the city that hosted the U.S.-North Korea summit—is helping to provide an answer.

Over the past decade, Singapore-based nonprofit Choson Exchange has trained some 2,000 North Koreans in entrepreneurship and business skills in dozens of courses in Pyongyang. It has brought more than 100 of those elites to Singapore, giving them a look at how authoritarianism and capitalism go hand-in-hand in this prosperous city-state.

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