The United States was in the pall of the Great Depression when Dorothea Lange began documenting its effects with stirring photographs of human hardship. By 1935 she was working for one of Franklin D. Roosevelt’s New Deal agencies, the Resettlement Administration (later the Farm Security Administration), bringing attention to the plights of sharecroppers, displaced families, and migrant workers. One day in Nipomo, California—driving home after a weeks-long assignment—the photographer stopped at a pea farm, where she came across a mother and her children, clearly desperate and close to starvation. Lange later recalled approaching them “as if drawn by a magnet.” The woman’s name was Florence Owens Thompson, and the result of their encounter was seven exposures, including Migrant Mother, which would become an emblem of the era and a landmark in the history of photography. Curator Sarah Meister’s thoroughly researched essay offers new insights into this iconic image’s creation and its enduring impact.