This book delves into the life and work of renowned twentieth-century photographer Harry Callahan, exploring his experimental approach and immense influence on photography. It examines Callahan's diverse subjects and techniques, from landscapes to portraits, through a detailed analysis of his fifty-year career. The volume draws on the Harry Callahan Archive at the Center for Creative Photography, offering a deep dive into his creative processes using negatives, proof prints, and contact sheets. Accompanying exhibitions at prominent institutions highlight his work. Published with the Center for Creative Photography, it includes rare, unpublished images, offering insights into Callahan's visual impact.