A great master of the early Renaissance, Piero della Francesca created paintings for ecclesiastics, confraternities, and illustrious nobles throughout the Italian peninsula. Since the early twentieth century, the rational space, abstract designs, lucid illumination and naturalistic details of his pictures have attracted a wide audience. Piero's treatises on mathematics and perspective also fascinate scholars in a wide range of disciplines. This Companion brings together new essays that offer a synthesis and overview of Piero's life and accomplishments as a painter and theoretician. They explore a variety of themes associated with the artist's career, including the historical and religious circumstances surrounding Piero's altarpieces and frescoes; the politics underlying his portraits; the significance of clothing in his paintings; the influence of his theories on perspective and mathematics; and the artist's enduring fascination for modern painters and writers.