Unifying thorium fuel cycle science with SMR engineering and deployment Thorium-based SMR development spans reactor physics, fuel cycle engineering, safety analysis, economics, and regulatory strategy, yet no single reference treats these domains as an integrated system. Thorium-Based, Small Modular Reactors, Systems Engineering, and Commercialization presents an end-to-end framework unifying thorium fuel cycle science with SMR design, digitalization, and global deployment, connecting theory directly to commercial practice. Coverage includes molten salt reactor architectures, TRISO fuel forms, digital twin integration, and autonomous reactor operation enabled by AI and machine learning. The book provides quantitative modeling for neutronics and thermal hydraulics, economic frameworks for commercialization, and supply chain roadmaps. An appendix consolidates reactor physics formulas and derivations, while in-chapter refresher sections reinforce foundational concepts. Readers will also find: Thorium-specific fuel cycle analysis addressing resource abundance, breeding potential, and proliferation resistance compared to conventional uranium pathwaysRegulatory and licensing considerations aligned with current NRC frameworks for advanced reactor design certification and deploymentStep-by-step derivations of core reactor physics equations with cross-references to foundational neutronics and thermal-hydraulic principlesGrid integration strategies and utility planning perspectives for deploying modular thorium reactors across diverse energy market contextsGlobal deployment roadmaps examining national programs, policy drivers, and commercialization pathways for thorium-driven SMR technologiesDesigned for nuclear engineers, reactor designers, advanced SMR developers, and graduate students in nuclear engineering, this reference also serves energy system modelers, utility planners, policy makers, and regulators seeking a technically grounded strategic guide to thorium-driven modular reactor commercialization.