There has been some progress during the past year in our ability to predict the circumstances under which severe lower respiratory tract infection is likely to occur in infants and children, to identify the viruses responsible for lower respiratory tract infection, and to provide protection for the patients most at risk. Our understanding of the requirements for a protective active immunizing agent for respiratory syncytial virus has improved. Increasing reports of Streptococcus pneumoniae resistant to beta-lactam antimicrobials have led to discussion regarding the appropriate means of screening for these resistant organisms and appropriate presumptive therapy when pneumococcal infection is suspected.