Professor G. W. A. Luckey, of the University of Nebraska, listing the causes of retardation, puts at the foot of his list "bad inheritance, unredeemable defects, physical and mental," and at the very top, "ignorance and indifference on the part of parents." Most investigators would evaluate these contrasting causes in precisely the same way. The inference, needless to say, is that we need never hope to bring about an appreciable diminution in the number of retarded children until parents are more fully enlightened as to their duties and responsibilities. It is therefore good to find that a nation-wide campaign of enlightenment is well under way, together with an ever-increasing extension of agencies for the work of rescuing the retarded and fitting them to achieve success in the school and in the world. Eight years ago there were in all the United States only three "clearing-houses for retarded children." These were the psychological clinic of the University of Pennsylvania, established by Professor Witmer in 1896; a civic psychological clinic, opened in 1909, in connection with the schools of Los Angeles; and the psychological clinic of Clark University, at Worcester, Massachusetts, established in the same year as a department of that university's splendid Children's Institute. To-day, as part of the regular activities of universities and normal schools, there are psychological clinics in more than a dozen States, including California, Colorado, Connecticut, Iowa, Kansas, Louisiana, Massachusetts, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Washington. At least four States--Indiana, Massachusetts, New York, and Pennsylvania--have psychological clinics in operation as adjuncts of hospitals. California, Illinois, Missouri, New York, and Pennsylvania have similar clinics in direct connection with the public school system. Ohio has one connected with a vocational-guidance bureau. And in some States--such as Connecticut, Illinois, and Massachusetts--psychological clinics are also in operation for the special purpose of aiding in the proper disposition of cases brought before the juvenile courts. Even more rapid has been the development of ear, eye, throat, and dental clinics for the needs of school children. As an outgrowth, too, of the discoveries of the past few years, there has been a widespread movement in the direction of establishing special schools and classes in which the retarded may receive the care necessary to enable them to make up for lost time, or, when this is out of the question, to equip them for as happy and useful a life as is possible under their exceptional mental limitations. Unquestionably a splendid beginning has been made in the warfare against retardation--a beginning not surpassed by similar effort in any foreign land, and certain to prove of great value to the American nation.