One of the most intriguing things of the think tank phenomenon is to determine if these research and policy action units have a real influence in the development of politics. In fact, most of them assure that they have a certain persuasive power over the decisions of government. It is the suppossedly main proof they offer when trying to justify their existence and in the funding process. However, due to the lack of systematic research on the think tank activities and the youngness of many institutes, it is still difficult to draw consistent conclusions about the topic.