The medical and paramedical personnel shows concern about clinical and epidemiological aspects of nosocomial infections, but pays also attention to their economical and legal aspects. The acquired infections in hospital bring about an overcost and social consequences. It is logical to study the ratio cost/efficiency insofar as the social and human dimension of illness and suffering are taken into account and the struggle and the prevention are not only seen- from their economical aspect. The legal liability of hospital or State health personnel is now well-know et the number of instituted proceedings is in continuous increase. The penal juridiction is the most common way. No negligence is permitted and nobody can be safe. The clarity and the dialog with the patients and their families are the best means to avoid a conflict prejudicial for everybody.