Renal imaging has become a fundamental part of clinical care for patients with kidney disease. Imaging strategies for the kidney have been evolving during the past hundred years and have been even more rapidly changing during the past couple of decades due to the development of modern computed tomographic techniques, magnetic resonance imaging, and more sophisticated ultrasonographic techniques, such as contrast-enhanced ultrasonography. Applying the correct radiologic study for the clinical situation maximizes the diagnostic accuracy of the imaging, and a judicious choice between techniques helps limit radiation dose and potential adverse events.