Coordinates a multi-centered clinical trial of a comprehensive intervention program to reduce asthma morbidity in inner city children; creates databases containing chemical structures and biological data in order to monitor and analyze developments in the chemotherapy of HIV and opportunistic infections; makes available information on clinical trials that evaluate experimental drug treatments; and supports training activities that include statistical and clinical research training on AIDS and emerging infectious diseases, as well as training in biostatistical and data management and methods for analysis of HIV vaccine trials.