The present study examines changes in defense maturity from mid to late life using data from an over 70-year longitudinal study. A sample of 72 men was followed beginning in late adolescence. Participants' childhoods were coded for emotional warmth. Defense mechanisms were coded by independent raters using the Q-Sort of Defenses (Roston et al., 1992, Ego mechanisms of defense: A guide for clinicians and researchers 217–233) based on interview data gathered at approximately ages 52 and 75. We examined psychosocial correlates of defenses at midlife, late life, and changes in defense from mid to late life. Overall, defenses grew more adaptive from midlife to late life. However, results differed on the basis of the emotional warmth experienced in the participants' childhoods. In midlife, men who experienced warm childhoods used more adaptive (mature) defenses; yet by late life, this difference in defensive maturity had disappeared. Men who experienced less childhood warmth were more likely to show an increase in adaptive defenses during the period from mid to late life.