Acute interstitial pneumonia (AIP) of feedlot cattle is a sporadically occurring respiratory condition that is often fatal. Affected cattle have a sudden onset of labored breathing. There is no confirmed effective treatment of feedlot AIP; however, administration of antibiotics effective against common bacterial respiratory pathogens and nonsteroidal anti-inflammatory drugs, especially aspirin, has been recommended. Protective strategies are not well defined, but efforts to limit dust exposure and heat stress; to ensure consistent formulation, mixing, and delivery of feed; and to identify and treat infectious respiratory disease in a timely manner may decrease rates of feedlot AIP.