The most recent and various researches, whether clinical, theoretical or therapeutic all agree on a central theme : in each encourter, which is always singular, between a person, a substance (or an object) and an environment, one cannot identify any specific or characteristic type of either personality structure or organization. At the most, scholars and clinicians may sometimes stress that defence mechanisms, the type of anxiety and most of the time the economics of such subjects as drug addicts, or persons liable to be addicted, remind one of what we find with borderline states but surely not exclusively. Quite a few common psychopatological traits, all stamped with the seal of regression is, besides, to be found with these patients with quite a few consequences to have to be followed in the therapeutic approach : a regression from desire towards quest, and from quest towards need, a regression of the mental towards the behavioral, and from the behavioral towards the bodily, a drive regression from aggressiveness towards violence and from libido to selferoticism. Within such a conceptual context, the autor wishes to stress the functions at work within this kind of psychopatological posture (or vulnerability) : namely, mainly two, i. e. the addictive function and the function of ordeal which will be both defined, described, analyzed and, if possible, linked with the several kinds of structures.