Self-induced disease can be difficult to diagnose and costly of time and money to investigate. The key is to think of the possibility. Five patients in whom the evidence for factitious rheumatological illness was strong are discussed and their histories, physical signs and family backgrounds are explored in relationship to factitious disease presenting in other fields. Young immature individuals seem most at risk and the discrepancy between physical signs and understandable pathological mechanisms may suggest the diagnosis. The outlook seems frequently poor.