This chapter discusses the origins of voluntaristics as a field of study, its global structure and growth trends, and the key substantive contents of the field beyond the transnational/international aspects reviewed. As a relatively young, organized, interdisciplinary field, voluntaristics does not yet have a fully settled global structure, such as physics and biology have. Nongovernment organisations (NGOs) are but one aspect of the larger, global, interdisciplinary field of research into all voluntary non-profit sector phenomena. Hypotheses thus deal with the origins phase, joining and membership, ideology, and structure and leadership, and could be applied to fundamentally deviant NGOs/international non-governmental organizations, such as transnational terrorist groups. Some research knowledge in voluntaristics can be useful in understanding NGOs in international relations. Various graphs in D. H. Smith show that many such aspects of voluntaristics as an academic discipline and field have been growing exponentially since about 1995.