The problem of deciding what is pertinent and what is extraneous is, then, obviously an important one. While the sociologist may be intensely interested in a subject matter pertaining to another science or craft, he has his own distinctive point of view, methodology, and objective, and since he cannot be an expert engineer, city manager, and sociologist all at the same time, he must accept the data of these other specialists when they happen to form the subject matter of his investigation. The sociologist is no more a housing specialist or a zoning specialist or a social case worker in a metropolitan social agency than he is an urban engineer or health officer, but he may have an important contribution to make to all of these activities, and may in turn acquire from these technicians a body of materials which shed light on his own problems and yield to sociological analysis. What is to be included or excluded from a sociological bibliography of the city depends upon the sociological definition of the city. Although the literature on the city extends as far back as the city itself, the subject is now being studied with renewed interest and with a new point of view. If we were compiling a complete bibliography we would most likely begin with the classical discussion of Socrates in the second book of Plato’s _Republic_ and follow the increasingly complex and scattered writings up to the present day, when we can scarcely find a science that does not have something to contribute to the subject. But this is not the aim of this bibliography. The attempt is here made to note just that part of the literature which has something to offer to the sociologist in the way of source material, point of view, method, and interpretation. A great deal, no doubt, has been included which is of little value. At the same time much has been necessarily omitted which is important. Some effort was made to avoid excessive duplication, but this attempt has not been wholly successful. The list of books and articles includes many works which were inaccessible at the time the bibliography was compiled, and whose contents could therefore not be examined. They are included because either the titles were suggestive or else the reputation of the authors merited attention.