This paper discusses the evidence of hand hygiene (mainly hygienic hand antisepsis) in reducing infections in different settings. In the hospital setting, there is convincing evidence that hand hygiene is effective in reducing nosocomial infections such as urinary tract infection, pneumonia, surgical wound infection and sepsis of in-patients, and in reducing the incidence rates of infection with methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). In long-term care facilities, there is limited evidence to prove whether hand hygiene is effective or not in reducing infections. In institutions such as schools, it is evident that hand hygiene is effective in reducing gastrointestinal illnesses and probably respiratory illnesses among healthy children and young adults. In the community, it is evident that hand hygiene is effective in reducing diarrhoea among healthy individuals within families. Unfortunately, despite the above evidence, doctors are constantly reported to have poor compliance in many studies. Therefore it is important for doctors to improve their compliance in hand hygiene whether they practise in hospitals or in their own clinics.link_to_subscribed_fulltex