The little-known life of York, the African American man enslaved by William Clark, and his contributions to the success of the Lewis and Clark expedition are examined in this carefully crafted Society of School Librarians International Honor Book. Award-winning author Laurence Pringle gives an accurate account of York's life—before, during, and after the expedition. Using quotations from the expedition's journals, he tells how York's skills, strength, and intelligence helped in the day-to-day challenges of the journey. Artists Cornelius Van Wright and Ying-Hwa Hu consulted with a Lewis and Clark expert to create thoroughly researched and stunning watercolor paintings of York's life.