With its limited force and funds it was not possible for the Children’s Bureau to extend its inquiries throughout the entire United States. It was therefore decided to make intensive studies of babies born in a single calendar year in each of a number of typical areas throughout the country that offered contrasts in climate and in economic and social conditions, the results to be eventually combined and correlated. It was necessary to restrict the choice of the first area to a place of such size as could be covered thoroughly within a reasonable time by the few agents available for the work. Johnstown, Pa., was the first place selected. It is in a State where birth registration prevails, and hence a record of practically all babies could be secured; it is of such size that the work could be done by a small force within a reasonable period, and it seemed to present conditions that could with interest be contrasted with conditions typical of other communities. Moreover, the State commissioner of health and the State registrar of vital statistics were both working zealously to enforce birth-registration laws; both were actively interested in reducing infant mortality, and they welcomed a study of the subject in their State. In Johnstown the mayor, the president of the board of health, the health officer, and other local officials all showed the same spirit of hearty cooperation and interest. Inasmuch as the study was confined to babies born in a single calendar year and work was begun in January, 1913, the latest year in which the babies could have been born and still have attained at least one full year of life was 1911. Work was begun on January 15, 1913, with the transcription from the original records at Harrisburg of the names and other essential facts entered on the birth certificates of babies born in 1911, and, if the baby had died during its first year of life, items on the death certificate were also copied. In the meantime the people of Johnstown through the press, and through the clergy in the foreign sections, had been informed of the purpose and plan of the investigation. Without the friendly spirit thus aroused and the interest manifested by the Civic Club and other organizations the work could not have been brought to a successful issue. The investigation was absolutely democratic; every mother of a baby born in 1911, rich or poor, native or foreign, was sought, and it is interesting to note refusals were met with in but two cases.