This study explored whether Smith and Lazarus' (1990, 1993) cognitive theory of emotion could predict emotional responses to an emotionally ambiguous real-life situation. Questionnaire data were collected from 145 women upon referral for cancer genetic risk assessment. These indicated a mixed emotional reaction of both positive and negative emotions to the assessment. Hierarchical regression analyses revealed that the hypothesised models explained between 20% and 33% of the variance of anxiety, hope and gratitude scores, but only 10% of the variance for challenge scores. For the previously unmodelled emotion of relief, 31% of the variance was explained by appraisals and core relational themes. The findings help explain why emotional responses to cancer genetic risk assessment vary and suggest that improving the accuracy of individuals' beliefs and expectations about the assessment process may help subsequent adaptation to risk information.