The invention relates to a method for determining a model of the environment of a vehicle, in which method an initial position estimate for the vehicle is acquired and map data are acquired, wherein the map data comprise information about the spatial arrangement of geographical areas, and the geographical areas are assigned to different area categories. Environmental data within an acquisition space is acquired, and objects are detected using the environmental data, wherein an object position and an object category are assigned to each detected object. The environmental model is determined using the detected objects. Assignment rules are provided which define the assignment of the object categories to the area categories, wherein the objects are detected in accordance with the assignment rules.