The paper, through a comparative approach, aims to analyze the applicability of competition law to the collective bargaining between trade unions and associations of entrepreneurs. In the perspective of the protection of workers rights, we propose, through a balacing of interests, to leave out some matters - i.e. wages, work hours and conditions - from the application of competition law. By contrast, we apply the principles of antitrust law to the restrictive effects on the relevant markets of goods and services, defining, at the same time, a taxonomy of possible anticompetitive effects on those markets.