Listeria monocytogenes displays a high degree of tolerance to a range of environmental stresses, an ability which contributes to its survival in minimally processed foods and its ability to cause an infection of the immune system. It can be shown that, in part at least, this ability to withstand harsh conditions is adaptive and relies upon a prior stress to induce the tolerance response. This is particularly significant given the increased reliance on the hurdle concept, or mild preservation procedures, employed by the food industry. This paper explores the extent to which Listeria can adapt to stressful conditions, and the molecular mechanisms which underlie this ability.