A 4 yr old, male castrated, St. Bernard presented to Cornell University Emergency Services with a 6 hr history of abdominal discomfort, retching and pytialism (hyper-salivation). He was seen by his referring veterinarian who diagnosed him with gastric dilatation-volvulus (GDV). On presentation to Cornell the dog was laterally recumbent and unresponsive. He was cyanotic and had increased respiratory effort and was tachycardic (225 bpm). Initial physical exam revealed poor peripheral pulses, a prolonged CRT (3 seconds) and pale mucous membranes. Blood work abnormalities included an increased PCV (60%)and a metabolic and respiratory acidosis as well as an increased lactate level (5.7 g/dL). Stabilization was attempted through multiple fluid boluses, gastric decompession and pain management. A right lateral abdominal radiograph was taken to confirm the diagnosis of a GDV, but also indicated the possibility of a concurrent mesenteric volvulus. The patient was immediately taken to surgery to correct the multiple volvuli. The purpose of this case report is to characterize the common clinical presentation, diagnosis, treatment, and prognosis of GDV and mesenteric volvulus in canines.