The subject matter of this paper is the model of personality developed by Otto Kernberg and the research tools designed on the basis of that conception. The paper presents the spectrum of diagnostic methods differing in terms of the level of structuralizing and the form in which they are applied. The first one constructed, the Structural Interview, due to the high requirements within psychoanalytical knowledge and clinical abilities for the individuals who apply it, initiated the development of subsequent methods. They include: the Structured Interview of Personality Organization (STIPO), inventory methods, and a clinician-rated instrument referred to as the Personality Organization Diagnostic Form (PODF). Within the scope of inventory methods, two principal tools for which Polish adaptations have been developed are presented, namely: the Inventory of Personality Organization of Kernberg and collaborators, and the Borderline Personality Inventory of Leichsenring. The existence of a broad spectrum of assessment methods of the personality structure makes it possible to take advantage of the conception of Kernberg in the realms of clinical diagnosis, scientific research, and recently also forensic psychology.