Fascination with the accurate depiction of human hair during the Renaissance can be traced back at least as far as Alberti (Della pittura) and is found later more emphatically in Leonardo (Trattato della pittura) and Castiglione (Libro del cortegiano). With Giorgio Vasari’s Vite, the depiction of hair (and facial hair in particular) becomes a touchstone for measuring artistic excellence. In both the 1550 and 1568 editions of this text, Vasari praises Michelangelo at length for the perfection he achieved while sculpting the beard of his Moses. Vasari himself returned to the question when he painted a unique Allegory of Sculpture on the walls of his Florentine home (1569–73). Examining some of these examples, both visual and textual, enables a better understanding of the important role that hair played in the paragone dispute, the competitive comparison between painting and sculpture. In this rather special moment when the practice and theory of art intersect, hairiness and its visual manifestations are revealed as being at the heart of artistic debates of the Renaissance.