"The theme of the 2015 National Convention is impact," says AIA spokesperson Matt Tinder over email. "We felt President Clinton would be an inspiration to attendees both in his role in government service and through his philanthropic efforts through the Clinton Global Initiative in which the AIA is a participant."
Clinton took office in 1993 and served two terms, and went on to found the William J. Clinton Foundation, today called the Bill, Hillary & Chelsea Clinton Foundation. He also started the foundation's Clinton Global Initiative (CGI) in 2005, which encourages members to develop Commitments to Action aimed at addressing world problems.
In 2012, the AIA launched one of these commitments, called Decade of Design, to research and develop best urban design practices. Partners with the AIA on this commitment include the Association of Collegiate Schools of Architecture and MIT's Center for Advanced Urbanism. "Together we are leveraging design thinking in order to effect meaningful change in urban environments through research, community participation, design frameworks, and active implementation of innovative solutions," wrote AIA CEO Robert Ivy, FAIA, in a 2013 CGI blog post.
Last year's Convention keynote speaker was Zappos CEO Tony Hsieh, after musician Pharrell Williams, who was initially announced as the convention's keynote speaker in March, cancelled due to a "scheduling conflict."