In recent reports, brucellosis has emerged as an important public health problem in the east Mediterranean region and Jordan is no exception. In 1986 and 1987, the minimal incidence rates per 100,000 persons in Jordan were 33.2 and 46.2, respectively, with no sex difference. Low incidence rates were confined to those below 4 and over 55 years of age. A seasonal incidence seen in 1986 was repeated in 1987 with maximal rates in the spring and summer months, exhibiting a strong connection with the lambing season. In-vitro sensitivity of 43 isolates of Brucella melitensis is presented. Endemicity in animals is discussed because of its direct relationship with the disease in man.