When this book was originally published in 1960, it was unique in two senses. Firstly, it presented the most detailed study of any British pressure group and it placed this detail in the framework of an original general theory of pressure group politics. Most of the book is devoted to a detailed analysis of the political activities of the British Medical Association (BMA). The author analyses the framework of medical policy within which the BMA acts; its structure and the political machinery it tries to influence; the attitudes toward medical politics both of doctors and the general public. He then examines the channels through which the BMA acts in politics and its effectiveness as a pressure group. In two theoretical chapters, the author also discusses the factors which determine the choice of channels through which pressure groups act; the reasons why they are involved in politics to a given extent; the factors which determine their effectiveness and whether pressure groups tend to support or undermine democratic systems. At a time when the BMA continues to exert pressure on the UK government, this book has an enduring relevance.