For lumbar spine surgery, there are instances when sacropelvic fixation and instrumentation are indicated. Mainly, sacropelvic fixation can be useful for complex clinical presentations such as high-grade spondylolisthesis, sacroiliac pain or dysfunction, and trauma. Sacropelvic fixation can also be helpful for long fusion constructs for multi-level lumbar arthrodesis and spinal deformities in the lumbar or thoracolumbar spine. To maximize the benefits of sacropelvic fixation, spine surgeons need to consider each patient’s unique anatomy, alignment, bone health, comorbidities, and past surgical history. Various screws and rod constructs can be used depending on the specific patient including traditional iliac screws, S2-alar-iliac (S2AI) screws, and kickstand rods with iliac screw. This chapter will provide an overview of the relevant anatomy, biomechanics, alignment, fixation zones, screws, and contemporary fixation techniques. Additionally, the utilization of robotics and navigation is discussed. Finally, several figures highlighting various fusion constructs are provided to give examples of fusion constructs for various clinical scenarios including high-grade spondylolisthesis, thoracolumbar and lumbar deformities, and for spinal osteotomies.