If your loved one is insisting that there are strangers in the house, they may be experiencing a delusion—a fixed, false idea. There are a variety of potential causes for this condition including changes in the brain that occur as a result of dementia. While these issues can be frightening for the entire family, there are strategies and techniques that can provide a solution for the family caregiver. Reacting calmly can help defuse the situation and preserve a person’s dignity.