The concept of dissociation has been used in confusing ways, due to a mixture of descriptive (`state') and explanatory (`process') definitions referring to different phenomena on divergent levels of abstraction. The interest in dissociative disorders is sketched against the historical background of the `fin de siècle' connection between hysteria, hypnosis, and trauma. Both investigators and therapists are warned for the `seductive' influence of dissociation and trauma theory, as well as for the dangers of `iatro-suggestion'.