Private enforcement has long been a central part of US antitrust law experience, while it has played minor roles or none at all in European competition law systems. This contrast is fundamental to understanding differences between European and US competition law and to assessing the potential consequences of increasing the role of private enforcement of competition law in Europe. It is also central to decisions about competition law development in much of the world, because in this respect most competition law systems in the world resemble European competition laws rather than US antitrust law.

In this essay, I examine the private enforcement of competition law in the US and Europe against the backdrop of efforts in Europe to rely more heavily on private enforcement in the enforcement of its competition law. As part of its so-called ‘modernization’ efforts, which went into effect on May 1, 2004, the European Commission seeks to reduce reliance on administrative authorities and to encourage those harmed by restraints on competition to bring private law suits in national courts. There is, however, widespread uncertainty about the prospects for successfully incorporating private litigation into European competition law systems. There is also uncertainty about which, if any, measures should be taken to enhance acceptance of private enforcement.

In assessing these issues, a comparative perspective can be of much value. It can provide a basis – perhaps the only sound basis – for making informed decisions.