The term “emerging diseases” has been used recently to refer to different scenarios, all of which indicate changes in the dynamics of disease in the population. Of the OIE List A diseases, major changes have been experi- enced with rinderpest, peste des petit ruminants (PPR), contagious bovine pleuropneumonia (CBPP), foot-and-mouth disease, African swine fever, lumpy skin disease, and Rift Valley fever. Rinderpest represents a success sto- ry of the 1990s, thanks to the programs of the Pan African Rinderpest Cam- paign (PARC). The situation has changed from that of the 1980s when rinderpest was widespread throughout most of Tropical Africa and the Middle East. PPR is a disease that has become of increasing importance throughout Tropical Africa and the Middle East. CBPP, which had previously been reduced to sporadic incidence within endemic areas, invaded new areas, caus- ing heavy mortality. African swine fever has extended to West Africa and to Madagascar, in both regions resulting in heavy losses. Climatic changes in both East and West Africa were associated with an upsurge of Rift Valley fever. Deficiencies in national veterinary services have contributed to failures in ear- ly detection and response; in many regions investigation and diagnosis services have deteriorated. The continuing structural adjustment program for national veterinary services will need to take into account their transformation from providers of services (e.g., vaccinations, medicines) to inspection and quality assurance services. Surveillance, early warning, and disease emergency pre- paredness will need to be pursued more vigorously in Africa and the Middle East as vital components of national veterinary services.