The doctor's use of deception in appropriate circumstances has commonly been considered a necessity of the medical art. Resistance to full and frank communication is typical of many traditionally Catholic countries, and particularly of Italy, a western country where Catholicism remains particularly influential. The Catholic teaching on truth and lies, and the problem of telling the truth to a severely ill patient is discussed. It is suggested that the contemporary Catholic model of gradually telling a terminal patient the truth, which looks reasonable and feasible in theory, is rarely followed in practice, as in the majority of cases the truth is not told tout court. Problems stem from the way in which medicine is currently practiced in Italy; from the synergism between Catholicism and the medical tradition's grounded paternalism; and from the ambiguity of the term 'hope'. Catholic ethics in fact recommends that the truth must be told without destroying hope, but the Catholic meaning of 'hope' is very different from its meaning in current language.