Thoughts about birth family, ethnic identity, and multicultural personality were investigated as predictors of dispositional authenticity (i.e., Authentic Living, Accepting External Influence, and Self-Alienation) among adult transracial Korean adoptees. Participants (N = 80) were transracial Korean adoptees aged 21 to 56 years (M = 33.9 years) who were adopted into White families worldwide between the ages of 0 and 66 months (M = 5.7 months). A two-step hierarchical regression model revealed that 1) thoughts about birth family and ethnic identity predicted variance in authenticity; and 2) the psychological health factor of the multicultural personality inventory predicted variance in subscales of authenticity above and beyond the variance accounted for by Step 1 predictors. Limitations, clinical implications, and future areas of research are discussed.