This is the first comprehensive and in-depth study of the earliest figural painting ever to have been produced in Flanders on a continual basis. Most of the manuscripts are Psalters, but Bibles, a Breviary, a Missal, a Netherlandic life of a saint, and yet other texts occur. Three main categories of illuminator are distinguishable: those working in Bruges, in Ghent, and, at least in part, for the circle of the counts of Flanders. The principal chapters and the catalog segments are organized around their individual contributions. An arrangement in time and place of the total body of work was obtained through a lengthy and rigorous process of comparison of figural, ornamental and writing styles, codicological and textual features. Several distinctive Flemish patterns of Psalter iconography have emerged; these are presented in tabular form with accompanying commentaries. A surprising amount of information about the early owners of the books, mostly well-to-do members of the laity, was yielded in the analysis for the manuscript catalogs.