Clinical pneumonia in goats is almost invariably preceded by some event or set of circumstances commonly referred to as stress. This very broad term, stress includes such factors as weaning, long distance hauling, weather factors including sudden temperature changes or low nigh- time with high daytime temperatures, poorly ventilated barns especially those heated in extremely cold weather, overcrowding, malnutrition, feed changes, parasitism and worming. The microorganisms (germs) which produce the actual disease process are often normal inhabitants of the respiratory tract. These microorganisms are prevented from causing disease by the normal animal's body defense mechanisms. The relationship between the body and the microorganism is sometimes a very delicate balance especially in the very young animal. Stressing factors can tip the balance in favor of the microorgansim and against the young animal.