Hospital-acquired infections (HAI) are notorious for the manner in which they complicate the course of the original illness, increase costs of hospital stay and delay recovery. This review will briefly outline the problems presented by HAI in developed countries and present evidence that Staphylococcus aureus and gram negative bacilli, the main causative agents, reach susceptible patients via the contact rather than airborne route, predominantly on the hands of hospital staff. Good hand hygiene could help reduce the economic burden and patient distress caused by HAI, but there is evidence that it is infrequently and poorly performed by nurses, the health care staff most frequently in continuous contact with patients. Possible reasons are explored in an attempt to identify strategies to improve hand hygiene.