Ambulation into potentially dangerous areas or away from necessary monitoring can be a problem for demented patients and their care providers. Current methods of controlling hazardous ambulation usually involve restraint, medication, locked doors, or physical intervention. Capitalizing on the observation that many demented individuals perceive two-dimensional patterns as barriers, we laid out masking tape in different grid patterns in an attempt to prevent ambulation through exit doors. The baseline condition (no tape) yielded a 98% exit-door contact for 8 demented male patients, but the addition of horizontal grids reduced exit-door contact to 42%. Often, complete prevention occurred at the first experimental trial. Advantages and cautions inherent in this approach to managing wandering by demented patients are discussed.