In summary the presurgical evaluation of the surgical patient is governed by the age of the patient, whether a major or minor surgical procedure is to be done, the amount of time available prior to surgery, and the financial limitations that the client places on the veterinarian following the complete physical examination. The aforementioned variables are then correlated with the patient's physical status to determine what presurgical clinical pathological evaluations are necessary. The patient's physical status is then correlated with the age of the patient, and categories of presurgical clinical pathological testing can be developed. These evaluations range from relatively simple inexpensive general screens, to emergency screens in which time is limited, and and to in-depth profiles that are biochemical and correlated with in-depth evaluations of the cardiopulmonary system, kidneys, and liver. By systematic presurgical evaluation of the surgical patient the surgeon should be better prepared to handle intraoperative and postoperative problems as they arise.