Capgras is the delusional belief that people in the sufferer’s life are not who they seem to be, but are identical duplicates who have been substituted for the originals. The copy looks just like the original, although the patient may sometimes notice minor and imaginary differences between the original and the copy, differences that the patient cites as confirmatory evidence that the person is indeed an impostor. Although Capgras was initially thought to occur only during psychotic episodes, it has now been recognized to occur in patients suffering from certain brain conditions as well. Capgras is one of several misidentification syndromes. Other misidentification syndromes, such as the Fregoli delusion and delusion of intermetamorphosis, also are discussed.