AFME CEO Simon Lewis faces myriad challenges as European regulators change rules governing the financial-services industry. Many of those rules, including a cap on bankers' bonuses and a tax on financial transactions, come with unintended consequences, Lewis says. For example, he is concerned that bankers facing a limit on bonuses will move elsewhere. "It's a backward step for Europe," Lewis said, warning that professionals will look to the US, the Middle East and Asia. "This is a very dynamic industry, and people can move."