Admission testing for conference interpreter training programmes traditionally focuses on skills directly related to the interpreting skills, and while soft skills, such as motivation, are recognised as important, they are not systematically tested or researched. The present study attempts to address this gap by exploring three traits and abilities, namely learning styles, motivation and cognitive flexibility, and to relate them to students’ self-selection for interpreting and to their success on final exams. Three tests were used to compare a group of self-selected interpreting students and applicants (n=32) and a subgroup of conference interpreting students (n=14) to a control group of undergraduate students (n=104), from among whom the majority of Lessius University College interpreting students are recruited: the Inventory of Learning Styles (Vermunt & Rijswijk 1987), the Achievement Motivation Test (Hermans 1968/2004) and the Wisconsin Card Sorting Test (Grant & Berg 1948). The results show that self-selected interpreting students are cognitively more flexible and are less negatively affected by anxiety. Compared to the control group, successful conference interpreting students, but not unsuccessful students, are cognitively more flexible and benefit more from some level of anxiety. Moreover, all conference interpreting students are less affected by stress than the control group and seem to have more clearly developed learning preferences.