A deep dive into the physiological and mechanical evaluation of pelvic floor disorders. The episode examines the hardware evolution of manometry from water-perfused catheters to high-resolution systems, and the standardization of dyssynergic defecation phenotypes via the London Protocol. It also reviews the diagnostic utility of the balloon expulsion test and compares the true physiological advantages of sitting fluoroscopic defecography against the anatomical clarity of supine MRI defecography.