A number of aspects related to vulnerability maps are discussed: the vulnerability concept, mapping purposes, possible users, and applicability of vulnerability maps. Problems associated with general-type vulnerability mapping, including large-scale maps, universal pollutant, and universal pollution scenario are also discussed. An alternative approach to vulnerability assessment—specific vulnerability mapping for limited areas, specific pollutant, and predefined pollution scenario—is suggested. A simplification of the vulnerability concept is proposed in order to make vulnerability maps more objective and by this means more comparable. An extension of the vulnerability concept to the rest of the hydrogeologicar cycle (lakes, rivers, and the sea) is proposed. Some recommendations regarding future activities are given.