This book discusses the cutting-edge intersection of Immersive Virtual Reality (IVR) and research on building occupants. It presents an innovative way of using IVR to revolutionise the comprehension of human-dimension responses to indoor built environments. A robust, innovative, and sequential protocol is defined and validated with a Virtual Environment against a real-world counterpart to provide readers with methodological approaches suitable for carrying out rigorous experimental research in building occupant research. This comprehensive guide provides also practical applications of the proposed guidelines to show the potential and effectiveness of IVR for conducting studies in different indoor environmental conditions in a multi-sensory approach. The book serves as a resource for researchers who want to exploit the full potential of VR in collecting reliable data useful for understanding human dimensions within built environments.