The paper addresses the question what the major challenges for the regulation of lobbying in Europe are. It attempts to disentangle this complex question by focusing, step by step, on three specific challenges. First, the problem of definition of lobbying, or the lack thereof, is considered. The paper argues that even though European countries started to regulate lobbying already two decades ago, they have still not managed to arrive at a useful definition of the field and activity of lobbying itself, which considerable hinders their pro-transparency regulatory efforts. Second, the paper looks at other anti-corruption legislation in Europe and its link to lobbying rules. The evidence shows that the level of corruption is not significantly affected by the presence or the lack of lobbying regulation; and this should be addressed by future regulatory efforts. Finally, the challenge of enforcement is treated in more detail and the development of lobbying in the US is cursorily compared with the European experience. Based on this comparison, tentative findings and policy recommendations are proposed, which might serve as the theoretical foundations for lobbying regulations in Europe and elsewhere.
