Nitroxyl donating compounds are administered prior to the onset of ischemia for the prevention and/or reduction of ischemia/reperfusion injury in subjects at risk for ischemia. Nitroxyl donors also are administered to organs to be transplanted for the prevention and/or reduction of ischemia/reperfusion injury upon reperfusion in a recipient. Nitroxyl donors include any nitroxyl donating compound. In particular cases the nitroxyl donor is a nitroxyl-donating diazeniumdiolate, such as Angeli's salt or IPA/NO.