This chapter explores spinal cord injury (SCI) rehabilitation, focusing on the latest advancements in brain-machine interfaces (BMIs), functional electrical stimulation (FES), spinal cord stimulation (SCS), and robotics. It begins with a discussion of SCI pathophysiology, detailing primary and secondary injury mechanisms, alongside the global incidence and demographic trends of SCI. The chapter emphasizes the importance of accurate neurological assessment, particularly through the American Spinal Injury Association Impairment Scale (AIS), in shaping effective rehabilitation strategies. The chapter then highlights both traditional and emerging therapeutic approaches, with a focus on the transformative potential of invasive and noninvasive BMIs. These technologies are instrumental in restoring motor function and improving the quality of life for individuals with tetraplegia. Innovations such as brain-spine interfaces (BSIs) demonstrate promising results in enabling natural movement, including standing and walking. Rehabilitation is discussed across acute, subacute, and chronic phases, stressing the need for a multidisciplinary approach. Advances in FES and SCS are revolutionizing SCI rehabilitation by facilitating movement, enhancing sensory feedback, and minimizing secondary complications. The chapter concludes by underscoring the interdisciplinary progress driving SCI rehabilitation, highlighting a future where enhanced mobility and independence are within reach, thanks to the integration of neuroengineering and clinical practice.