This book comprehensively explores lignocellulosic bioethanol production, emphasizing sustainable engineering, process optimization, and regulatory frameworks. It explains the transition from fossil-based fuels to bioethanol, highlighting its potential as a renewable and eco-friendly alternative. The chapters cover a wide spectrum of topics, starting with the fundamentals of biomass-to-bioethanol conversion, including feedstock logistics, lignocellulosic chemistry, and experimental design. It introduces advanced metabolic and omics-based genetic engineering strategies to enhance microbial efficiency in bioethanol production. The book further explores artificial intelligence-driven process modelling, fluid rheology, and unit operations in bioethanol refineries. Additionally, it integrates the concept of circular economy, sustainability assessments, and economic evaluations to establish a holistic approach to bioethanol production. It focuses on environmental legislation, compliance, and national and international regulatory frameworks governing biofuels. This book is an essential resource for researchers, academicians, and professionals in biotechnology, biochemical engineering, renewable energy, and environmental sciences. It also serves as a valuable reference for policymakers and industry leaders seeking insights into the technological advancements and regulatory aspects of sustainable bioethanol production.