Beginning in the late 1970s with the first reports of two-dimensional, gray-scale ultrasonography used to image small-animal abdominal organs, the question of whether to use contrast radiographic or ultrasonographic techniques for urogenital assessment has become increasingly important. In the last five to seven years, the volume of veterinary literature on ultrasonographic imaging equals or exceeds that on contrast radiographic imaging of the small-animal urogenital tract. While the advantages of ultrasonographic over contrast radiographic imaging are obvious for some situations (eg, renal failure or paraprostatic cyst), no overviews critically comparing these techniques have been published to our knowledge. With the increasing availability of ultrasonographic equipment in private veterinary practice, choices between these imaging techniques must be made. Imaging the kidney and the prostate gland are discussed because both techniques are applicable to these organs. Our intent was to determine which of these techniques would be appropriate for the common clinical conditions. This article addresses the advantages and disadvantages of both techniques for renal and prostatic imaging. The perspective provided is based on ten years of clinical experience with both techniques by each of the authors. Clinical scenarios and specific diseases are discussed and the consensus of the authors on the procedure(s) of choice for these situations are described.