US agricultural and companion animals are very vulnerable to the introduction of exotic and emerging animal diseases (EEAD). These diseases could occur through unintentional introduction (the risk of outbreaks grows as free trade increases), could occur through the deliberate introduction of disease agents (bio-terrorism or agro-terrorism), or could emerge as new diseases. EEAD, for the purpose of this course, are defined as those animal diseases that are reportable in the US. This includes diseases on the Office international des épizooties (OIE) List A, selected diseases on List B that either are not found in the US or are reportable, and selected emerging diseases. Some of the exotic and emerging diseases are considered to be foreign animal diseases because they do not occur in the US. Others are found in the US but are under eradication programs. Some are zoonotic and must be monitored and controlled to protect human health. Many of these diseases are important causes of animal suffering and are economically very important. It is essential that veterinarians be familiar with these diseases and have access to accurate, concise information about their salient characteristics.