This chapter is an in-depth analysis of the JDP organization. First, it discusses the theories relating to party organizational models and embraces the approach which sees party organizations as strategic responses to electoral markets and wider political conflicts. Then, the chapter analyses various theories and concepts regarding party typologies and proposes to understand them on a continuum between mass-based (an organizational model relying on ideologically driven, tightly controlled, mass membership forms of organization and labour-intensive campaign techniques) and elite-based (an organizational model relying on personalistic leadership, political marketing techniques and capital-intensive campaign techniques) ideal types. Then, the chapter focuses on the JDP’s local presence, its membership structure and its internal organizational operations. Such operations include public opinion surveys and consultations, as well as actors, such as party co-ordinators and women’s branches. Given the party’s linkages with its electorate and its internal operations, the JDP can plausibly be viewed as lying in the middle of a continuum between the mass-based and elite-based models. The chapter argues that Erdoğan’s JDP is a hybrid party or, more precisely, a 'personalistic mass party', combining a tightly controlled, mass membership organization, active year-round, with personalistic leadership and political marketing techniques.