Taking as a starting point assumption that the processes concerning personality ought to be explored in systematic and holistic way, the main question was posed about internal (personal), and external (environmental), as well as relational (person-environment) factors and mechanisms which stimulate change in personality or preserve continuity and stability in personality during middle adulthood. deals with (1) content or (2) coherence of the patterns of cognitions, affects and behaviors or (3) change of a principle underlying organization of such patterns. A comprehensive model of science of personality introduced by McAdams (2001) was proposed as a base for integration of knowledge about personality development and change in personality on three levels: dispositional traits, characteristic adaptations, and life stories. On the first level the changes are described mainly in terms of increasing consistency of the traits. On the second level change in personality is regarded as a result of cognitive-affective processes, purposive behaviors and organization of the self system. On the third level personality change and development is stimulated by narrative identity and intentional activity which give direction, coherence and meaning of life. The Gauguin syndrome and posttraumatic growth were presented as the examples of such changes. The considerations lead to conclusion that looking for explanation of change in a principle underlying pattern (coherence) of cognitions, affects and behaviors we need to explore dynamic processes which operate among three levels of personality.