In studying the Doctrina Christiana of 1593 there are four general problems which we shall discuss. First, we shall give a physical description of the book. Secondly, we shall trace chronologically the bibliographical history of the Doctrina, that is, we shall record the available evidence which shows that it was the first book printed in the Philippines, and weigh the testimonies which state or imply to the contrary. Thirdly, we shall try to establish the authorship of the text, and lastly, we shall discuss the actual printing. It hardly needs be told why so few of the incunabula of the Philippines have survived. The paper on which they were printed was one of the most destructible papers ever used in book production. The native worms and insects thrived on it, and the heat and dampness took their slower but equally certain toll. Add to these enemies the acts of providence of which the Philippines have received more than their share--earthquake, fire and flood--and the man-made devastations of war, combined with the fact that there was no systematic attempt made in the Philippines to preserve in archives and libraries the records of the past, and it can well be understood why a scant handful of cradle-books have been preserved. The two fires of 1603 alone, which burned the Dominican convent in Manila to the ground and consumed the whole of Binondo just outside the walls, must have played untold havoc upon the records of the early missionaries. Perhaps the only copies of early Philippine books which exist today, unchronided and forgotten, are those which were sent to Europe in the 16th, 17th and 18th centuries, and may now be lying uncatalogued in some library there.