The paper presents an ontological conceptualization of the phenomenon of extremity, which is considered in the context of personality transformation in the trans-ordinary world. Methodological principles and scientific logic of conceptualization are proposed and specified in the following concepts: the experience of being and non-being, personality work, meaning and behavioral personality work, positive and negative extremity, the meaning of life and the meaning of death, the nature of the construction of psychological effects of extremity — psychic trauma and personal transformation.

The paper investigates multi-direction of extreme cases impact on an individual. Interdependence of two extremity aspects psychological and professional is traced. It is information extremity that is thought to be the most dangerous for personality and society.