This investigation used data from Loehlin and Nichols's (1976) study of over 800 sets of twins to examine evidence for the heritability of three facets of empathy: empathic concern, personal distress, and perspective taking. Expert judges first identified sets of adjectives, included within Loehlin and Nichols's original data, which reflected each empathy construct; these items were then validated in an independent sample. Comparisons of the responses given to these items by identical and fraternal twins in the Loehlin and Nichols investigation revealed evidence of significant heritability for characteristics associated with the two affective facets of empathy--empathic concern and personal distress--but not for the nonaffective construct of perspective taking. This pattern is consistent with the view that temperamental emotionality may underlie the heritability of affective empathy.