PURPOSE: To review the anatomy and function of the sacroiliac joint (SIJ), as well as the pathophysiology, clinical presentation, diagnostic criteria, and treatment options for SIJ dysfunction. METHODS: The SIJ serves an extremely crucial function in mobility, stability, and resistance against shear forces. Joint mobility becomes increasingly limited with age-related cartilaginous changes that begin in puberty and continue throughout life. Pain can also be localized to the SIJ itself, known as SIJ dysfunction. A literature review was performed on the anatomy, etiology, risk factors, diagnostic modalities, and treatment options for SIJ dysfunction. RESULTS: SIJ dysfunction is an under-recognized source of low back pain. Dysfunction can result from various clinical conditions, as well as abnormal motion or malalignment of the joint. Diagnosis and evaluation of SIJ dysfunction are difficult, with use of physical maneuvers and image-guided anesthetic injection. Non-operative treatment options are considered first-line due to high surgical complication rates. Such options include conservative management, radiofrequency treatment, nerve blocks, and articular injections. Surgical management involves open and percutaneous approaches. CONCLUSION: With the aging nature of the population, SIJ dysfunction has emerged as an extremely prevalent issue. Current research into the pathophysiology and risk factors of SIJ dysfunction is extremely important for planning preventative and therapeutic strategies. Various treatment options exist including conservative management, radiofrequency, nerve blocks, intra-articular or peri-articular injections, and surgical fixation. Improved diagnostic methods in clinical practice are thus critical to properly identify patients suffering from SIJ dysfunction, plan early intervention, and hasten return to function. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.