Microscopic and gross hematuria present unique and difficult diagnostic and management challenges in the already complex general surgery patient. This article provides the general surgeon with relevant knowledge in the pathophysiology, anatomy, etiologies, workup, and treatments of hematuria. In addition common causes of hematuria that may be encountered by the general surgeon (including trauma, urinary tract infection, urolithiasis, and malignancy), the difficult to manage clinical situation of clot urinary retention is presented. This article provides a urologic framework of thinking for the clinician to best manage a general surgery patient who has hematuria.