Abstract The purpose of this review is to discuss the relatively recent revival of interest in bacterial interference, particularly the use of Bifidobacterium spp. in nutrition, for treatment and prevention of disease in medicine and commercial food products by using recently developed technology. In 1910, Metchnikoff (1) first put forward the idea that the regular consumption of fermented milks might offer health benefits, the possible prophylactic and/or therapeutic properties of yogurt and related products have been the subject of much speculation. New fermented dairy products containing Lactobacillus species and Bifidobacterium spp. have been developed and marketed in Europe, North America and the Far East. The potential “health-promoting” properties of Lactobacillus acidophilus is well documented, but possible roles of ingested bifidobacteria have not been reviewed much. Bifidobacteria are normal inhabitants of the human and animal gut, and newborns are colonized within days after birth. The population seems to be relatively stable until advanced age when it has been reported to decline. Although the population of bifidobacteria in the intestine is stable, it is influenced by diet, antibiotics, stress etc. Bifidobacteria were first described by Tissier in 1899 (2) as predominant flora in breast-fed infants. This review will consider the characteristics, ecology and role in human systems, the therapeutic and prophylactic activities of Bifidobacteria, and the potential pharmaceutical and fermented products manufactured using bifidobacteria and advanced technology. The facts and the results of the some of the experiments done by different authors and the current areas of research interest and future development have also been reviewed.