Using the concept map method, this study revealed patient characteristics that are important for treatment selection decisions in patients with personality disorders. Concept mapping is a specific type of structured conceptualization process and describes the underlying structure of specific phenomena. The method uses qualitative and quantitative methods. In this study, we integrated a literature investigation with the opinions of 29 experts in the field of treatment allocation and/or personality disorders. Our goal was to reduce and describe the number of patient characteristics that are important for treatment allocation in personality disorders. The concept map procedure resulted in eight patient characteristics: (1) severity of symptoms, (2) severity of personality pathology, (3) ego-adaptive capacity, (4) motivation and capacity for a therapeutic alliance, (5) patient’s social system, (6) social demographic variables, (7) traumata, (8) treatment history and physical examination. This report describes in detail the concept mapping procedure and the outcomes are discussed.