This paper is stimulated by the need to develop an ecclesiological method that is capable of describing and analysing the diverse self-understandings that characterize global Pentecostalism (or any Christian Church). It begins by observing the limitations of idealist approaches to ecclesiology, and instead proposes a concrete ecclesiological method. Concrete ecclesiology will include the narrative of particular Churches and movements, describe the explicit and implicit self-understanding that accompanies this narrative, and assess ecclesial transitions. Since the Church is a human and divine community, analysis will incorporate theological categories and the human sciences. Consequently, the paper considers how the ecclesiologist might appropriate the multifaceted discipline of sociology. The goal is an ecclesiology that is not reduced only to ideal categories, but that is capable of analysing the complex reality of indigenous Pentecostal Churches.