It is investigated whether killing delicts as a "solution" of conflicts between partners are the expression of a fateful situative restraint, or whether it is the personal disposition of the committer which entails killing. The fundamentals of the discussion are examinations of 98 criminals with killing delicts, 36 of whom "solved" a conflict in partnership by killing the partner. The 36 separation crimes can be subdivided into four groups according to the prevailing causes. 16 happened due to the partner's intention to leave, 14 due to humiliation and severe offence, 3 due to material self-interest, and 3 in states of delusion. For each of the four groups a typical representative in his constellation of situation and personality is described. Generalized, it will be questioned under which circumstances someone develops the will to kill the partner, and who possesses the capability to realize this will. It can be shown by systematical exploration of their personality by means of objective personality testing procedures that almost all criminals who have committed murder show a conspicuous structure of personality. Hysterical and/or sociopathic properties predispose a person to acts of personally-impertinent or personally-short-sighted violence.