<jats:p> Background: This study aimed to evaluate the effectiveness of environmental control interventions using an integrated chip tag monitoring system for a frontotemporal dementia (FTD) patient. </jats:p><jats:p> Method: The subject was a male FTD patient (Pick type) with reversed sleep—wake cycles. For a 2-week period, the doors to all patients' rooms in the unit were kept open as a form of environmental control, and in the following 2 weeks, all doors were kept closed (intervention A). To increase his activity levels, a staff walked with him for 2 weeks (intervention B), while all the doors to patients' rooms in the unit were kept closed. </jats:p><jats:p> Result: In intervention A, daytime ambulation increased, whereas nighttime ambulation decreased significantly. During intervention B, nighttime ambulation increased significantly. </jats:p><jats:p> Conclusion: Environmental controls seem to be effective for restoring sleep—wake cycles in even an advanced-stage FTD patient, whereas exercise program by the staff aggravated the problem. </jats:p>