Introduction and objective: The data regarding personality disorders is ambiguous; it is estimated that their prevalence may range from 6% to 30%. In Poland, there is a lack of up-to-date and precise data on the occurrence of personality disorders, partly due to diagnostic difficulties. Currently implemented classifications of mental disorders take into account the dimensional nature of personality disorders. The project reported on below is based on the dimensional approach and has three main objectives. Firstly, it aims to determine the possibility of distinguishing groups that present different levels of personality functioning. Secondly, it seeks to analyse differences between the identified groups in terms of socio-demographic variables, experiences related to the treatment of mental health disorders, traumatic experiences in childhood and adolescence, as well as self-harm and suicidal behaviours throughout life. The third goal is to present a practitioner’s perspective on the treatment of individuals with personality difficulties and disorders depending on their severity. Materials and methods: The study was conducted by a research panel (N = 1,030; representative sample). The level of personality functioning was measured using the self-report Level of Personality Functioning Scale–Brief Form 2.0 according to DSM-5 (LPFS-BF 2.0). Results: The results indicated the possibility of distinguishing three groups presenting different levels of personality functioning. These groups differed significantly in variables including age, gender, education, size of place of residence, depressive/anxiety symptoms, and history of traumatic experiences. Conclusions: The findings of the study may have significant implications for the development of effective mental health prevention strategies and tailored medical care for individuals with personality difficulties and disorders.

personality disorders, mentalisation, group psychotherapy, LPFS-BF 2.0, dimensional diagnosis