The thesis explores the emerging realm of “living” fungal-based composites in architecture, examining a shift from methods that form and dry mycelium (fungi's rootlike networks,) - referred to here as "nonliving", to methods based on mycelium's unique growth processes, referred to here as "living". By utilizing the biological functions of mycelium in its living state, this generation of living methodologies addresses the challenges and limitations faced by earlier mycelium applications and further advances the potential of mycelium in the construction and architecture industry. For the past decade, there has been a growing interest in the bio-fabrication of mycelium due to its sustainable, structural, and economic benefits. Claimed as one of the leading classes of biomaterials, mycelium-based composites building material alternatives that promote low-carbon emission and are compostable. Despite gaining recognition, the integration of mycelium in architecture remains limited, with the composite mostly applied to installation and exhibition scale projects. By drying and killing the organism, the predominant brick-and-panel approach of mycelium research of the last decade has tended to fix mycelium in the shape of a given formwork rather than privileging mycelium's unique growth capacities. Earlier research on using mycelium in construction relied heavily on traditional construction methods and replicating conventional materials without fully utilizing its capability for self-healing, self-growth, and self-organization. By analyzing five case studies that reflect this generation of recent "living" mycelium research, this thesis aims to demonstrate the benefits of preserving mycelium in its living state to translate their innovative methodologies to mainstream architecture applications. Specifically, the thesis investigates five strategies and illustrative mycelium research projects that foreground mycelium’s unique biological properties in its living state: Myco-welding of conventional mycelium-based blocks (La Parete Fungina), Fibre reinforcement and welding of 3D-printed components (Mycera), Bio-collaboration of mycelium-based composite and bacterial cellulose (BioKnit), Bio-tectonic of living mycelium (Mycelium Tectonics), and Senso-aesthetics of mycelium’s natural processes (Mycelium Rope). The thesis identifies three key characteristics of this generation of research across these projects: 1. biological utilization (the active harnessing of mycelium's unique biological processes), 2. integral and lost formwork (the use of formwork that becomes a permanent part of the structure), and 3. material understanding and visual acceptance (the understanding of technical knowledge and aesthetic appreciation of mycelium as a building material) . Each case study's research goals, design intentions, methodologies, and reflections will be explored to provide insights into the potential of living mycelium architecture. The concepts presented in the paper challenge traditional notions of today’s static architecture and propose a dynamic and living framework capable of adapting to its environment. The study positions living mycelium as a model for resilient and adaptive structures. This approach offers new insights for sustainable construction that harness the self-repairing, regenerative properties of living organisms. The purpose of this comparative research is not to undermine the existing development of non-living mycelium architecture but rather to expand the knowledge of the unique natural functions of living mycelium toward sustainable design practices.