Summary: The frequency of prescribing analgesics and administering them for the treatment of apparent postoperative pain in 243 dogs and 15 cats was evaluated. Surgeries performed on the animals evaluated included limb amputations, limb-sparing bone cancer resection, thoracotomy, cervical vertebral instability repair, and humeral fracture repair. Only 1 cat was treated once with an analgesic after surgery, and cats were not evaluated statistically. Dogs undergoing amputation, limb salvage procedure, or thoracotomy were more likely to be treated than dogs undergoing the other surgeries. Ninety-six (40%) of the 243 dogs were under the influence of an analgesic at any time during their postoperative hospital stay, and 69 dogs (28%) received 1 or more doses of an analgesic after recovery from general anesthesia. One hundred thirty-three dogs were cared for in the intensive care unit (icu) immediately after surgery. Written instructions for treatment with an analgesic were given for 61 of those dogs, and 50 were given at least 1 dose of the prescribed analgesic. Dogs cared for in the icu were twice as likely to be given an analgesic as dogs cared for in the surgery ward. The estimated duration of analgesic effect exceeded 8 hours in 46 (19%) of 243 dogs. Small and juvenile dogs were least likely to be treated. Interns and residents were twice as likely as faculty to administer analgesics. Most written interpretations of pain behavior observed in the icu were made on the basis of vocalizations. Half of the dogs for which medical record comments suggested moderate to severe pain were not given an analgesic. The most frequently administered analgesic immediately following surgery was oxymorphone, followed by butorphanol and morphine. Aspirin was never administered to dogs in the icu, but was used in 10 dogs that were in the surgery ward for > 74 hours.