By exploiting their genetic and metabolic capacity, lactic acid bacteria can be used to generate a variety of products from milk sugar lactose other than the archetypical lactic acid. This review will outline the different genetic and metabolic engineering strategies that can be applied to lactic acid bacteria to realize this valorization of lactose. Attention will be given to the controlled production, by lactic acid bacteria, of enzymes that convert lactose. In addition, we will summarize the progress and potential of redirecting the metabolic flux from lactose to produce existing, modified, and novel metabolites. Examples to be discussed include the production of compounds that are relevant for the flavour, texture, and health aspects of foods.