Chicago Classification v4.0 (CCv4.0) is the updated classification scheme for esophageal motility disorders using metrics from high-resolution manometry (HRM). Fifty-two diverse international experts separated into seven working sub-groups utilized formal validated methodologies over two-years to develop CCv4.0. Key updates in CCv.4.0 revolve around a more rigorous and expansive protocol that incorporates different positions and provocative testing, a refined definition of esophago-gastric junction (EGJ) outflow obstruction (EGJOO), an increased threshold for the diagnosis of ineffective esophageal motility and inclusion of a description of baseline EGJ metrics. Further, the CCv4.0 sought to define motility disorder diagnoses as conclusive and inconclusive based on associated symptoms, the use of provocative testing and corroborating supportive testing with barium esophagram with tablet and/or functional lumen imaging probe. These changes attempt to minimize ambiguity in prior iterations of Chicago Classification and provide more standardized and rigorous criteria for patterns of disorders of peristalsis and obstruction at the EGJ.