Summary.One hundred teachers in training in the Department of Education, University of Manchester, were tested with measures of abilities, personality, interests, values and general culture, and provided a considerable range of biographical information. The predictive power of these various measures was examined in terms of three main criteria—final teaching mark, final theory mark, and award of the Graduate Certificate in Education. Degree class was the best single predictor of theory mark and of final award. A personality questionnaire (Cattell's 16 P.F.) was the best single predictor of teaching mark. The successful student tended, apart from academic qualifications, to have a high level of general culture, high conscientiousness (16 P.F., factor G), to have tender‐minded attitudes to education, and to participate fairly widely in social activit