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Mayor Rahm Emanuel hailed the selection of both architectural firms, saying they had track records of creating innovative civic projects. He called the presidential center project a "once-in-a-lifetime opportunity" for all Chicagoans.
Nevertheless, the architects will face myriad challenges — whichever site is chosen. They range from maintaining the integrity of the historic parkland to striking a balance between the Obamas' desire for a welcoming facility and the need to meet federal security mandates.