The activities of the World Health Organization (WHO) during 1955 were surveyed in the anuual report to the World Health Assembly and to the UN of the WHO Director-General, Dr. Marcoline G. Candau. During 1955, Dr. Candau stated, substantial results had been achieved in three categories of programs: the fight against communicable diseases, the strengthening of national health services, and the raising of standards of education and training for all types of health personnel. Malaria, tuberculosis, poliomyelitis, and trachoma were among the communicable diseases towards the eradication of which WHO activities had been directed, with in many instances considerable progress. However, it had become increasingly evident that the beneficial effects of such campaigns against disease could only constitute concrete gains for public health if national health services could be effectively strengthened, and during 1955 a large part of WHO's work had continued to be devoted to that aim, in all regions but particularly in the Americas, southeast Asia and the eastern Mediterranean. In the development of national health services, particular attention had been devoted to such matters as the principle of program integration, nutrition and health education, changes in health services necessitated by the aging of populations, mental health, and environmental sanitation. In regard to education and training of health personnel, an effort had been made in the regions to increase the use of all methods which had proved their value in the past, including direct training of health personnel at all levels, provision of fellowships for study abroad, assistance to institutions and the sponsoring of international conferences, training courses and seminars.