Citrus is the most widely produced fruit in the world and it is grown in more than 80 countries. Due to its varied and wide chemical composition as a consequence of its nature, citrus is an exceptional feedstock to the designing and assessing of biorefineries. A wide spectrum of products are obtained from citrus, which nowadays are extracted and purified into essential oils, antioxidants and other compounds. This book provides research on the production, consumption and health benefits of citrus fruits. The first chapter begins with an overview of citrus based refineries. Chapters two and three discuss hesperidin and narirutin, which are citrus flavonoids. Chapter four studies the use of citrus residues as raw materials for biomolecules and energy. Chapter five collects information from published works about the alternative use of citrus residues as efficient and promising adsorbents in clean water technology. The final chapter examines citrus genetic improvement.