Starting in his seminar La relation d'objet, Lacan distinguishes between three kinds of lack, according to the nature of the object which is lacking. The first one is Symbolic Castration and its object related is the Imaginary Phallus; the second one is Imaginary Frustration and its object related is the Real Breast; the third kind of lack is Real Privation and its object related is the Symbolic Phallus. The three corresponding agents are the Real Father, the Symbolic Mother, and the Imaginary Father.