Threatcasting is a foresight methodology that examines the worst of potential future changes by imagining and crafting a fictional (but very plausible) story of a person, in a detailed setting, experiencing a threat. In this dissertation, I investigate the processes and techniques of threatcasting, focused primarily on the post-analysis phase, and demonstrate it as an open methodology that can embrace varied ways to analyze raw data and seek conclusions. I incorporate best practices of narrative and thematic analysis, qualitative analysis, grounded theory, and hypothesis-driven theories of inquiry. I use interviews from futurists trained on threatcasting ways of thinking and compare two case studies - one using a grounded theory approach on the future of weapons of mass destruction and cyberspace and the other using a hypothesis-driven approach on the future of extremism - to investigate the efficacy of different theoretical approaches to analysis. I introduce definitions of novelty and ways to assess how a novel finding may have more impact on the future than it appears at first glance. Often, this impact comes more from what is not present in threat scenarios than what is included. Finally, I illustrate how threatcasting, as a practice, is a valuable contribution to those in a position to be responsible architects of a better future.