In the United States, effective control of brucellosis in animal populations, primarily cattle, has resulted in the reduction of the number of human infections from 6,321 in 1947 to 231 in 1969; however, brucellosis continues to be a significant occupational hazard to workers in meat packinghouses and to others associated with the meat-processing industry. Employees in packinghouses accounted for 68% of the human cases reported in 1969. Most of these infections are related to infected swine. Elimination of the disease from this source is in sight within this decade, but it will require the cooperative efforts of all those involved in activities related to disease control. Cases of human brucellosis as the result of infection with Brucella neotomae have not been reported in the United States. A few cases of human infection with Brucella melitensis have been reported in recent years, but most were not acquired from indigenous sources.