Combining three major facets of Alfonso's final and most personal work, this holistic study utilizes a philological approach involving codicology, hermeneutics, history of art, iconology, paleography, and philosophy. Like his Cantigas de Santa María, with its vast musical, poetic and artistic dimensions, the Book of Games is a largely unexplored multi-media treasure trove of knowledge about thirteenth-century games, art and symbolism as well as personal information about the Wise King himself. Chapter I explains the historical chess, dice, backgammon and mill games ands offers the first complete English translation of the Book. Descriptions and diagrams of all 144 games, including PowerPoint presentations of all 103 chess problems using a font specially designed to match the original manuscript exactly, are presented in an international format which brings these challenging and entertaining games to life. Chapter II surveys all 151 illuminations, exploring their cultural value and identifying portraits of Alfonso, his wife, his lover, his children, his friends and his sources. Alongside traditional medieval iconography, these may represent some of the earliest known likenesses in medieval portraiture and some of the first private, non-iconographic images of a Spanish king. Chapter III interprets the literal, allegorical, tropological and anagogical meanings of each game according to the Hermetic principle "As above, so below" as well as the numerological symbolism and didactic structure reflected in the book's Scholastic structure. Each game in the Libro de los juegos contains a clue "pora los entendudos e mayormientre pora aquellos que saben la Arte de Astronomia" (fol. 95r) for understanding the connection between astrology and human affairs. At the end of his ill-starred life Alfonso saw reflected in the microcosm of these games, the determinism inherent in the workings of the universe. By studying the patterns in these games, Alfonso hoped to discover how best to play the game of life using both his "seso," or skill, and his lucky number seven. The numerological and astrological significance of the numbers seven and twelve, present in the entire work's structure and especially the concluding games, relate the Book of Games to the Alfonsine legal, scientific and religious corpus.