Preservation and transfer of power within the ruling family is of fundamental importance to any monarchy. Clearly specified principles of royal succession are a condition on which depends the stability of this authority and the stability of the state in which it is exercised. Constitutional monarchies have the question of succession regulated by a number of legal clauses preventing any dynastic disputes from becoming an open conflict that would divide society into opposing camps. The case was very different in Hellenistic monarchies because the practically limitless power their kings enjoyed left only to them the decision to name the successor, a decision often taken amid pressures and intrigues. The striking testimony of the disastrous consequences of struggles for power within the ruling family are the dynastic contentions in the states of the Seleucids and the Ptolemies. In Hellenistic monarchies, the generally accepted and applied principle was for the reigning king to name his son as successor. A customary practice, it very often saw departures from it, which is why in effect the transit of power was not always smooth and free from conflict. The monarchy's person-centered nature meant that the king could just as well transfer authority according to his choosing, as if it was part of his personal property. Various rulers took decisions about succession, sometimes leading to dramatic events that affected the future of respective ruling houses. How portentous such decisions could be is confirmed by the history of the Hasmonean family.