This paper describes a type of parental dysfunction—intermittent decathexis—which apparently has not previously been reported although it occurs frequently, to varied extent. The dysfunction is introduced by some of the clinical material that originally brought it to the author's attention, is contrasted with the more usual parental investment in their children. Its relationship to depression and then to aggression is next clarified. Examples of the manifestations of having been intermittently decathected are offered from both child and adult analyses as well as the impediments it provides for a child's progressive emotional development. Finally, the evidence is presented which led the authors to conclude that metapsychologically intermittent decathexis is a primitive defensive manoeuvre.