Negativistic phenomena in the treatment of neurotic children and adults are examined and distinctions are made among negativism, negation, and denial. Clinical vignettes exemplifying various forms of negativism are presented and viewed as expressions of developmental, defensive, or characterological aspects of the personality. Hartmann’s seminal concepts of the genetic fallacy, change of function, and secondary autonomy are employed. The addition of a developmental view provides a broader context within which to view the patient’s behavior and on the basis of which to formulate interpretive interventions.