The definitive biography that unlocks the remarkable story of Vivian Maier, the nanny who lived secretly as a world-class photographer, featuring nearly 400 of her images, many never seen before, placed for the first time in the context of her life. Vivian Maier, the photographer nanny whose work was famously discovered in a Chicago storage locker, captured the imagination of the world with her masterful images and mysterious life. Before posthumously skyrocketing to global fame, she had so deeply buried her past that even the families she lived with knew little about her. No one could relay where she was born or raised, if she had parents or siblings, if she enjoyed personal relationships, why she took photographs and why she didn't share them with others. Now, in this definitive biography, Ann Marks uses her complete access to Vivian's personal records and archive of 140,000 photographs to reveal the full story of her extraordinary life. Based on meticulous investigative research, Vivian Maier Developed reveals the story of a woman who fled from a family with a hidden history of illegitimacy, bigamy, parental rejection, substance abuse, violence, and mental illness to live life on her own terms. Left with a limited ability to disclose feelings and form relationships, she expressed herself through photography, creating a secret portfolio of pictures teeming with emotion, authenticity, and humanity. With limitless resilience she knocked down every obstacle in her way, determined to improve her lot in life and that of others by tirelessly advocating for the rights of workers, women, African Americans, and Native Americans. No one knew that behind the detached veneer was a profoundly intelligent, empathetic, and inspired woman-a woman so creatively gifted that her body of work would become one of the greatest photographic discoveries of the century.