Factitious disorder imposed on another (FDIA), also known as fabricated or induced illness by carers (FII), and first named as Munchausen syndrome by proxy (MSbP), is a condition in which a caregiver creates the appearance of health problems in another person, typically their child. This may include injuring the child or altering test samples. The caregiver then presents the person as being sick or injured. Permanent injury or death of the victim may occur as a result of the disorder. The behaviour occurs without a specific benefit to the caregiver.

The cause of FDIA is unknown. The primary motive may be to gain attention and manipulate physicians. Risk factors for FDIA include pregnancy related complications and a mother who was abused as a child or has factitious disorder imposed on self. Diagnosis is supported when removing the child from the caregiver results in improvement of symptoms or video surveillance without the knowledge of the caregiver finds concerns. Those affected by the disorder have been subjected to a form of physical abuse and medical neglect.

Management of FDIA may require putting the child in foster care. It is not known how effective therapy is for FDIA; it is assumed it may work for those who admit they have a problem. The prevalence of FDIA is unknown, but it appears to be relatively rare. More than 95% of cases involve a person's mother.

The prognosis for the caregiver is poor. However, there is a burgeoning literature on possible courses of therapy.

The condition was first named as "Munchausen syndrome by proxy" in 1977 by British pediatrician Roy Meadow. Some aspects of FDIA may represent criminal behavior.