Theoretical formulations of the castration complex have changed as psychoanalytic theory has developed. The author briefly reviews the literature and asserts that analyzing the set of fantasies related to potential or imagined castration continues to be clinically quite important. Understanding these unconscious fantasies provides a window into the individual's experience of his or her body in relation to those of important others throughout development. A case is provided to illustrate this, and to discuss the ways in which several different ways of thinking about castration fantasies contributed something essential to this analysis.