Aggression is an integral part of all conceptualizations of suicide. Using Freud’s economical (quantitative) point of view of metapsychology and her revised drive theory, the author offers a conception of aggression that integrates the assumptions of different psychoanalytic schools. Aggression is understood as the forceful way of asserting one’s needs and desires whenever they are or seem to be thwarted. In economic terms, aggression is conceptualized as the intensified effort (increased energy quantities) of the preservative and/or sexual drives to reach their goals. This view sheds new light on the presuicidal state of mind when an important object (or its substitute) is lost. The extraordinary rise of drive energies, activated in a desperate and unrelenting effort to reach the unreachable object – sometimes in addition to the power of Nachträglichkeit – overwhelms and breaks the containing function of the psychic structures. Such breach causes the unbearable pain the suicidal person wants to escape from. Some clinical suggestions derive from this conception.