This study proposes an analysis about the evolution of the professional secrecy in Europe and in the United States. Examining how this institution applies within the antitrust and anti-money laundering legislation, this contribution aims at deepening its juridical nature and its “resistance” in comparison with other values, which common regulations deem as worthy. Further, this analysis highlights some criticalities of the professional secrecy within Italian legal system, particularly the relationship between secrecy and confidentiality and the protection of professional secrecy in criminal matters.