This chapter explores the intricate functional anatomy of the human spine, an engineering marvel that balances the dual demands of support and mobility. It delves into the complex structure of the spine, detailing the vertebrae, intervertebral discs, muscles, ligaments, and nerves. The chapter begins by outlining the general approach to understanding the spine’s anatomy and its division into cervical, thoracic, lumbar, and sacral regions, each with unique characteristics and functions. A detailed examination of the bony and muscular elements of the spine, including the vertebrae and their specific features across different spinal regions, provides insight into the spine’s mechanical strength and protective capabilities in maintaining posture and enabling motion is thoroughly discussed. Furthermore, it focuses on a comprehensive examination of the functional sagittal plane alignment of the spine, emphasizing its evolution and clinical significance. Clinical aspects include the significance of spinopelvic indices in diagnosing and treating spinal disorders. This chapter also emphasizes the complexity of defining “normal” spinal alignment, and highlights the necessity of personalized assessment. It concludes with the spine’s multifaceted role in human anatomy and movement, stressing the importance of understanding spinal structure for health maintenance. Understanding the spine’s functional anatomy is crucial for diagnosing and treating spinal disorders and is of paramount importance for professionals in sports medicine.