One of the first principles of public library management is that of adjusting it to the needs of its public, by whom and for whose benefit and pleasure it is supported by the municipality. Upon this proposition there has been no disagreement, as it is self-evident. Questions of general policy arise when we attempt to decide what is beneficial and what is detrimental, just how far we may go to supply books for special and limited use, and just how far we may respond to the popular taste in the demand for the expenditure of public funds for pleasure. The breadth and limitation of book buying should be determined by the needs of the public rather than from the ratings of the books which are being published. We should find the books that are best fitted for the people who are to use them, rather than to try to fit the people to the books which we may consider as the most desirable. The questions so often raised as to the admittance to the library shelves of some books of fiction of doubtful morals or the latest piece of erotic literature seem very trivial when we consider the problems that face us in the broad field of library work. The library is a public enterprise for public good, and not merely a coöperative scheme for the purpose of obtaining cheap reading, nor a bibliographical storehouse. The important question is whether the books we are asked to buy will serve any legitimate end of library service. Most of our American cities resemble each other in the exceedingly complex character of their population, each of whose varied elements has more or less claim on the services of the public library. While it is not possible to classify definitely the residents of a city for library purposes, there are certain large groups which we may recognize. In the first place, the public library has to serve, as libraries of all times have served, those who have had all the advantages of systematic education--those in the learned professions and in other walks of life who have had given to them, through college and university training, a wider vision than that of the average citizen; those who have had given to them at least the knowledge of the existence of the store of accumulated thought and of the records of the past. Upon these more fortunate ones rests the responsibility, in a large measure, of carrying the torch of knowledge and civilization a little farther with each generation. The public library does not pretend to act as a guide to this part of the community, but it must serve as its laboratory and as its source of supply.