This study investigated types of change that occur over time in the psychopathology of narcissistic patients. Baseline scores on the Diagnostic Interview for Narcissism of 20 patients, clinically diagnosed as having narcissistic personality disorder, were contrasted with their scores 3 years later by means of t tests and chi-square statistics. The authors then compared these changes in narcissism with the patients' accounts of their life events during the interval between the two assessments. A significant decrease in the overall level of pathological narcissism was found, particularly in the areas of interpersonal relations and reactiveness. At follow-up, 60% of the subjects had reached the cutoff score on the diagnostic interview that indicated significant improvement, and 40% remained unchanged, with a high level of pathological narcissism. A high baseline level of narcissism in interpersonal relations was associated with absence of change at follow-up. Examination of life events in the interval between assessments suggests that changes in pathological narcissism are related to three kinds of experiences: achievements, new durable relationships, and disillusionments. The instability of narcissistic psychopathology found in this study raises questions about the construct validity of narcissistic personality disorder as a diagnostic category and about the core construct of pathological narcissism.