Since he won last month’s general election, British Prime Minister David Cameron has been sounding out fellow leaders for their views of his plan to renegotiate the U.K.’s relationship with the European Union.

So far, most responses have been guarded because his demands aren’t yet specific. But, from Mr. Cameron’s announcements so far, we can already outline five main areas where he will seek concessions, and even suggest, based on conversations with officials and experts, how his demands may be accommodated.

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