ABSTRACT This investigation examined personality development during the transition from adolescence to adulthood using the brief form of the Multidimensional Personality Questionnaire (Patrick, Curtin, & Tellegen, 2002). Parent and self-reports of personality were obtained in 1994 (average age=17.60 years), and self-reports were obtained in 2003 (average age=27.24 years). There was evidence of both differential stability and normative changes in the direction of increased functional maturity during this transition. Moreover, adolescents with more mature personalities in 1994 tended to show fewer personality changes from 1994 to 2003. These maturity-stability effects held when parent reports were used to assess personality. All told, there was evidence of both stability and change in personality during the transition to adulthood.