This paper studies the most extreme forms of miscarriages of the psychoanalytic treatment and the resistances that induce them. The fact that these resistances are most frequently unforeseeable before the beginning of the treatment is emphasized. We reaffirm the necessity to distinguish between these miscarriages of treatment and negative therapeutic reactions, the fundamentals of which are not discussed here. (PsycINFO Database Record (c) 2006 APA, all rights reserved) (journal abstract)