Respiratory syncytial virus is a regular winter visitor that is highly contagious among persons of all ages. It is the major nosocomial pathogen on infant and toddler wards, and has recently been recognized as also causing appreciable nosocomial illness in the elderly. Control of the spread of this virus has been difficult, but transmission appears to require close contact via large-particle aerosols or via fomites. Environmental conditions affect the survival of the virus on varying surfaces and skin, but self-inoculation after touching contaminated surfaces appears to be an important mode of transmission.