In honor of the 150th anniversary of W. E. B. Du Bois’s birth in Great Barrington, Massachusetts, the University of Massachusetts Library has prepared a new edition of Du Bois’s classic, The Souls of Black Folk. Originally published in 1903, Souls introduced a number of now-canonical terms into the American conversation about race, among them double-consciousness, and it sounded the ominous warning that “the problem of the Twentieth Century is the problem of the color-line.” In a new introduction, Shawn Leigh Alexander outlines the historical context of this critical work and provides rare documents from the special collections archive at the Du Bois Library at the University of Massachusetts Amherst. Unlike Du Bois’s more scholarly work, Souls blends narrative and autobiographical essays, and it continues to reach a wide domestic and international readership. This moving homage to black life and culture and its sharp economic and historical critique are more important than ever, resonating with today’s unequivocal demand that Black Lives Matter in the twenty-first century.