Humans weren’t the only first responders to the site of the World Trade Center on Sept. 11, 2001. Search dogs played an invaluable role in helping emergency crews locate and rescue survivors, and like their human counterparts, they often worked days without taking a break.
Hundreds of dogs helped, but only a handful still survive. Photographer Charlotte Dumas set out to take portraits of them to commemorate their service more than a decade later, compiling them for a book, called Retrieved.
(SEE the photos from MSN)