Probiotics have been the subject of intensive research, mainly focusing on bifidobacteria and lactic acid bacteria. However, there is evidence that dairy propionibacteria also display probiotic properties, which as yet have been underestimated. The aim of this paper is to review recent data which report probiotic characteristics of dairy propionibacteria and to distinctly organise them based on the experimental strategy employed: ranked from in vitro evidence to in vivo trials, which is a new approach. In addition to the selection criteria for probiotics in areas such as food safety, technological and digestive stress tolerance, many potential health benefits have been described which include modulation of microbiota and metabolic activity in the gut, modulation of intestinal motility and absorption, impact on intestinal inflammation, modulation of the immune system and potential modulation of risk factors for cancer development. The robust nature of dairy propionibacteria towards technological stresses should allow their future use in various fermented probiotic foods. Among the probiotic properties of dairy propionibacteria described in the literature, some of these properties are different from those reported for bifidobacteria and lactic acid bacteria. However, supplementation with dairy propionibacteria in randomised, placebo-controlled, double-blind human trials has mainly involved mixtures of propionibacteria with probiotic bacteria from other genera. Clinical studies involving the use of dairy propionibacteria alone are lacking. Such studies will allow the specifically observed health benefits to be attributed to dairy propionibacteria. This, in turn, will allow the investigation of the synergistic effects with other probiotic bacteria or beneficial food components.