In making clinical decisions concerning the urogenital system, the emergency department physician has many different diagnostic tools at his or her disposal. Choosing the appropriate diagnostic study can often be difficult. For well over a thousand years, the initial step in assessing almost any urologic condition has been to examine the urine. Thankfully, this has progressed from a gustatory approach to the modern urinalysis. There is certainly a great deal of information that may be gleaned from the urinalysis, but the physician must also be mindful of its limitations. Overuse of the urinalysis can result in unwanted and unhelpful information. Although IVP is still the study of choice in assessing the functional status of the kidney, the introduction of CT and ultrasound technology to clinical medicine has revolutionized the emergency department assessment of the urogenital tract. CT and ultrasound can help differentiate between the urologic emergencies and the various surgical conditions that can mimic them.