The book is a comprehensive study and complete catalogue of Danish-born journalist Jacob A. Riis's influential images, emphasizing his role in early 20th-century social reform photography in America. Riis, renowned for documenting urban poverty as a reporter for the New York Tribune, used his camera to highlight the conditions of tenement housing during massive immigration. This scholarly work results from over two decades of research, compiled from five major repositories, including previously unpublished photographs and notes. Author Bonnie Yochelson offers a novel perspective on Riis, proposing him as a radical publicist rather than a skilled photographer. Published with the Museum of the City of New York, this book supports an exhibition that traveled between notable locations in 2015 and 2016.