It will be noted that the same problem may be mentioned in several addresses, though usually from a different angle. The entire avoidance of repetition would have necessitated the abandonment of the lecture form, and would, I believe, have diminished the utility of the volume. The table of contents and index render cross-reference easy. Those wishing to ascertain fuller details on most of the problems discussed in the present volume may refer, I think with advantage, to my annual reports as Medical Officer of the Local Government Board, England, and to my four special reports on Maternal and Child Mortality, which also were issued as English Government publications. British experience is only partially applicable in the United States, the almost complete Home Rule in each State creating a new and interesting problem in efficient national public health administration. Nevertheless a review of events in Great Britain cannot fail to be useful in America, which is faced with similar problems. The main lines of public health administration in Great Britain have proved their value by their success. There has been local independence with a minimum of central control, and the people’s representatives in every area have been made to realize their commercial responsibility. The mistakes made in permitting the multiplication of small and inefficient public health authorities, in allowing official medical work to be divided respectively between different local and central authorities, in sanctioning the creation of _ad hoc_ authorities for special work, in associating state medicine with monetary insurance against sickness, and in not securing that insurance shall directly assist the prevention of sickness, have been largely the mistakes of politicians and of central authorities. These mistakes involve the retracing of steps and the undoing of the mischief resulting from ill-advised action. In view of these conflicting events, the marvellous achievements secured by public health authorities are the more noteworthy.