This prospective study was carried out in the department of infectious diseases of Gaziantep University between January 1997 and December 1999 to evaluate the epidemiological, clinical and laboratory features of brucellosis in south-eastern Turkey. One hundred and twenty consecutive patients with active brucellosis were enrolled. The commonest way of transmission was ingestion of milk products from diseased animals. Brucella melitensis was isolated in the specimens of 31 (45.5%) of 68 patients. The commonest abnormalities on physical examination were fever (66.6%), hepatomegaly (63.3%) and splenomegaly (56.6%). Osteoarticular involvement was found in 34 patients (28.3%). Fifteen (12.5%) patients had ocular involvement. Hepatitis, orchiepididymitis, pulmonary involvement and meningitis were found in one (0.8%), four (6.8%), three (2.5%) and one (0.8) patient, respectively The commonest haematological abnormalities were relative lymphomonocytosis (71.6%) and anaemia (36.6%). In conclusion, brucellosis continues to be a common health problem in communities where the consumption of unpasteurised dairy products is common. Since prevention is as important as early diagnosis in reducing the morbidity of brucellosis, we suggest that improving current health policies with additional educational programmes is essential.