Her preference to photograph strangers began while she was still at Yale School of Art, when she placed newspaper advertisements asking for "people for portraits".
Writing in The New Yorker Andrea Scott called the portraits "an alloy of vulnerability, bravado, and nerves," and a view of the American dream turned inside out.
She would photograph strangers in Los Angeles and San Francisco against stark white walls as a backdrop.
[11] She befriended several of the subjects and made a video piece called "The Believers" with them [12] Speaking of her Modesto photography, Grannan said that she was inspired by a childhood best friend who lived in the streets as a teenager and died in her 20s; Grannan spoke of her photographs not so much as activism but as a mutual flow of connections and generosity.
[13] Sean O'Hagan, reviewing her 2009 London exhibition The Westerns, described her work as "never less than intriguing" with "an otherworldliness here that sets her apart from her influences.