This paper reports on wayfinding in dementia, in particular the ability to develop decision plans for solving wayfinding problems in unfamiliar settings. Fourteen patients diagnosed as having mild to moderate dementia of the Alzheimer type (DAT), and 28 normal elderly were asked to reach a destination in a large hospital setting, and to return to the point of departure. Verbalizations of all subjects were recorded, transcribed, and content-analyzed in order to identify the decisions made during the trip and to establish their functional relationships revealing their planning abilities. Results showed that all DAT patients failed to reach the destination and return to the point of departure without errors. Compared to normal elderly subjects, their overall decision plans were poorly structured, indicating basic problem-solving disorders. However, they were able to solve well-defined problems and develop sub-plans in routine situations when the necessary information was readily available. Nondiscriminatory reading of irrelevant information was also observed and tended to interfere with problem-solving.