US President Barack Obama and First Lady Michelle Obama leave after speaking at an event presenting the 2011 Pritzker Architecture Prize to Eduardo Souto de Moura, a 58 year old architect from Portugal, at the Andrew Mellon Auditorium in Washington, DC, June 2, 2011. The annual award honors a living architect whose built work demonstrates a combination of talent, vision and commitment, which has produced consistent and significant contributions to humanity and the built environment through the art of architecture. AFP PHOTO / Saul LOEB (Photo credit should read SAUL LOEB/AFP/Getty Images)