This chapter discusses the radiological imaging of the most common infections of the spine and focuses on pyogenic, non-pyogenic and post-procedural infections. Plain radiographs are usually the initial imaging modality used in patients with back pain. Computed tomography (CT) is less sensitive and specific than magnetic resonance imaging (MRI) in the detection of spondylodiscitis, but provides better planar detail of bony abnormalities than plain radiographs. Pathogens can infect the spine by three routes: hematogenous spread from an infected microembolus, direct inoculation, or from contiguous tissues. Clinical factors such as advanced patient age, spinal trauma and diabetes mellitus increase the susceptibility to postsurgical spine infections. MRI is used to monitor response to treatment in patients with spine infection. The chapter suggests that MR changes may persist or even worsen during treatment despite clinical improvement.