This new facsimile edition of the Portfolio of the 13th-century Picard artist Villard de Honnecourt is the first ever to be published in color. The thirty-three leaves are reproduced at actual size from high-quality color transparencies to ensure the best possible color reproduction of the drawings. One can now see variations in inks and quill strokes, traces of preliminary drawings, and corrections made by the artist. This study is also the first to give a thorough description of the condition of the leaves, analysis of each drawing in the portfolio individually, and new transcriptions and literal and free translations of the inscriptions. The opening chapter covers the history and physical condition of the portfolio, including reassigning "hands" to text found on the leaves. The author analyses the tools and inks used, Villard's drawing technique and style, and evaluates Villard as an artist-draftsman. Chapter II, the body of the book, is devoted to detailed analyses of the leaves, one by one, and their drawings and inscriptions. These analyses are of interest to those concerned with medieval technology and theology as well as to those interested in medieval art and architecture. Chapter III is a new biography of Villard that challenges the many wild speculations of the last century and a half about Villard, separating obvious fiction from possible fact. Barnes analyzes in detail Villard's drawings of different Gothic buildings and makes a case for Villard having been a lay representative of the cathedral chapter at Cambrai, one of the buildings Villard drew. An extensive bibliography of Villard studies and a glossary of Villard's technical and artistic terms complete this important new study.