Twenty-five consecutive patients found to have brucellosis at Security Forces Hospital during one year from September 1984 through the end of August 1985 have been reviewed. The diagnosis was based upon clinical features plus Brucella antibody titers of 1:160 or greater, determined by agglutination of sera with a killed bacterial suspension. Of these patients, 92% were Saudi, 68% were males [age range 19-50 years] and 32% were females [age range 10-25 years]. Bone or joint pain was the chief complaint for 60% of the patients, and 40% presented with pyrexia of unknown origin [PUO]. The average total duration of illness was 14 days for patients presenting with PUO, and 18 weeks for patients presenting with bone or joint pain. The white blood cell [WBC] count averaged 7, 000/mm3 with a range of 3, 800 to 13, 400/mm3 Positive blood cultures for Brucella were obtained in 40% of the patients. Bone films showed abnormalities in 33% of the patients that presented with bone or joint. Bone scans performed on patients with bone or joint were abnormal in 60%. Most of the patients were treated with rifampin and co-trimoxazole over at least three months. All of these patients experienced complete clinical recovery. Relapses occurred only in patients that discontinued their medication prematurely