In urology, PVR stands for post-void residual volume, which is the amount of urine left in the bladder after a voluntary void. PVR is a diagnostic tool used to evaluate bladder function and detect underlying pathology. It can be used to evaluate many disease processes, including but not limited to neurogenic bladder, cauda equina syndrome, urinary outlet obstruction, mechanical obstruction, medication-induced urinary retention, postoperative urinary retention, and urinary tract infections. A PVR can be determined via urinary catheterization, a portable dedicated bladder scanner, or a formal ultrasound examination. When used in conjunction with the American Urological Association (AUA) Symptom score and a 24-hour voiding diary, the PVR can provide the clinician with a clear picture of the patients bladder activity, functionality, and correlation with symptoms leading to an evidence-based diagnosis which then guides appropriate directed therapy. A PVR is a valuable diagnostic tool for evaluating patients with various urological symptoms such as urgency, frequency, incomplete emptying, weak urinary stream, suprapubic pain or pressure, and bladder overactivity, incontinence, hesitancy, or stranguria.