While defining appropriate roles for political advisers is a highly relevant topic in most democracies and especially in EU NMS, as well as candidate and CARDS countries today, surprisingly little comparative information exists. To fill this gap, in Autumn 2005, the Sigma Programme launched a questionnaire-based study to collect country experience, as well as a series of seminars on the topic. The first part of this publication provides an overview on the role of political advisers and their relationship with civil servants in OECD countries. In a second part, detailed country chapters on political advisers in Denmark, Poland, Portugal, Spain, as well as Great Britain are presented.