Vivian Maier has received the kind of attention most photographers and artists can only dream of – multiple monographs, documentary films, commercial gallery representation, extraordinary public interest, and now a biography. However, all this activity and acclaim has occurred posthumously. In her lifetime Maier’s mammoth output, estimated at 150,000 photographic exposures and hundreds of reels of silent movie footage, wasn’t known. She didn’t take photographs for public consumption, for publication, or for exhibition – she took them for herself. Photography was her obsession, but its outcomes came perilously close to total obliteration. Maier – ill, old, and poor – was unable to meet the payments on her storage units in Chicago and so, without her knowledge, the contents were sent to auction where small-time collectors purchased her undeveloped films, negatives, and prints. This alone explains her attraction; the mysteriousness of her origins and her secretive life as the ‘nanny photographer’ have only increased it.