Inventing Illness or disability for social, emotional or financial gain has been known to occupational therapists since the early days of professional practice. Despite this, there is little literature that is relevant to therapists' practice. In medicine, the condition has attracted a number of labels from ‘polysurgical’ to ‘conversion hysteria’. More recently, the subject has received renewed popular interest because of media coverage of dramatic and newsworthy cases of Munchausen's syndrome and Munchausen's syndrome by proxy. Within the medical literature, the 1994 edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) now Includes a section titled ‘Factitious disorders’. The definition of these disorders is given as ‘physical or psychological symptoms which are intentionally produced or feigned in order to assume the sick role’. In occupational therapy, evidence from the letters page suggests that such clients are known and talked about, but that there are few procedures or guidelines for dealing with them. A tension is apparent between therapists who view these clients as wilfully behaving badly for gain (incorrigible rogues) and therapists who view these clients as having profound psychological problems (sad cases). The differing implications for service delivery, where one or other of these beliefs is strongly held, are divisive. In this article, the nature of factitious disorders in occupational therapy is explored, using examples from research into ethical dilemmas and information from respondents to the letters page of this journal. From these it appears that therapists are skilled at identifying such clients, but how and by whom the client should be confronted and treated remains unresolved In a number of workplaces.