Research on cognitive maps as mental representations of real world environments can considered to be confronted with two central problems: (1) The attainment of an adequate theoretical formulation of the ambiguous concept of cognitive maps, and (2) the development of a well-suited methodology for externalizing these mental maps. On the basis of model-theoretical considerations, a 'method-comparison strategy' for research on cognitive maps is proposed. An experimental design comparing different methods for gaining access to mental representations of city structure will be out- lined, the results of which will be reported at the conference.