During the last 4 years, 20 cases of clinical melioidosis were diagnosed in the geographical area between Tully and Thursday Island. Sixteen were diagnosed by culture of Pseudomonas pseudomallei, and four by positive serology with appropriate clinical features. Most cases occurred during or after a heavy wet season. All patients were adult, and males predominated. Farmers and stockmen represented predisposed populations due to their prolonged soil contact. Ten patients were white Australians, six were Aborigines and four were Torres Strait Islanders. Twelve cases were first diagnosed by positive blood culture and four by sputum culture. The primary site of infection was pulmonary in 14 cases, genitourinary tract in one case, subcutaneous tissues in one case, and joints in two cases. In cases of fulminating infection metastatic abscesses were commonly found in many organs; typically lungs, liver, kidneys and spleen. Six patients had acute fulminating disease and died. Fourteen patients successfully responded to appropriate therapy, but relapse occurred in three, all of whom had an alcohol problem and showed poor drug compliance. The presence of diabetes mellitus in six patients confirmed the important known association of these two diseases. In three fulminating and four subacute infections the serology was negative at the time of diagnosis by culture. Antibiotic therapy for the different forms of this disease is reviewed, and a laboratory protocol for the rapid reporting of positive culture results is included.