During the early years of the 20th century children were often employed in exhausting and dangerous industrial trades. This image shows a group of boys of various ages, many of them not yet teenagers, lining up for work. The photographer Lewis Hine is credited with having established the modern documentary style of photography in the United States. He trained as a sociologist and teacher, then became a ‘social photographer’ and worked with organisations campaigning for reform. Many of his images of children at work were made from 1906 to 1918 for the National Child Labor Committee, New York, which was active throughout the country.