From the American Library Association:
The American Library Association (ALA) hosted its 2017 Annual Conference & Exhibition, June 22-27, in the association’s home city of Chicago. The conference was attended by more than 22,700 librarians, library workers and library supporters (including more than 6,500 exhibitors) from across the world.
Past ALA Annual Conference Attendance
Overall 16,597 librarians, library workers and library supporters attended the 2016 ALA Annual Conference in Orlando, Florida.
The overall number includes 4,995 exhibitors representing 758 companies and organizations.
2015 San Francisco and 2014 Las Vegas
The 2015 ALA Annual Conference in San Francisco had a total attendance (participants and exhibitors) of 22,696 while the total attendance at the 2014 ALA Annual Conference in Las Vegas was 18,626
2013 ALA Chicago
Total attendance was 26,362 (including 15,918 attendees and 6,125 exhibitors).
See Also: Video: Hillary Rodham Clinton on “Libraries Making a Difference” (ALA 2017 Closing Keynote)
See Also: 2017 Annual Conference Video Playlist (22 videos via ALA on YouTube)