As part of the German Party Member Study 2009, around 9,400 members of the six parties represented in the German Bundestag were surveyed about their sociodemographic characteristics, their attitudes and motivations, as well as the nature and extent of their intra-party involvement. The book provides insights into the inner workings of German party democracy based on this study: Who becomes a member of German parties? To what extent and in what ways are citizens active within them? What political attitudes do party members hold, especially in comparison to the electorates of their parties? How satisfied are members with their parties? How do they respond to dissatisfaction, and what intra-party reform needs do they identify?.