[Family constellations in theory and practice: on symmetry and complementarity].

The concepts of "symmetry" and "complementary" of social systems in Bateson and Toman are compared. Bateson describes self-reinforcing cycles of formation of equality and inequality of social systems, whereas Toman means compatibility and incompatibility of social systems according to sibling positions of individuals involved. His concept is important to an empirical family psychology, family diagnosis and family therapy. A family diagnostic case-study shows the practical application.