This study investigated the perception of principals on how the factors of subject mastery, teaching methodology, personal characteristics, and attitude toward students affect the performance of teachers at higher secondary level in the Punjab. All principals of higher secondary level in the Punjab were part of the population of the study. From the population, 120 principals were selected as the sample. A questionnaire was developed and validated through pilot testing. The data obtained were tabulated and analyzed by using statistical techniques of mean and standard deviation. The major conclusions of the study were that the factor of subject mastery was perceived to be influencing the performance of teachers maximally, but the factor of attitude toward students was affecting the performance of teachers minimally. The remaining two factors--teaching methodology and personal characteristics--were perceived to be at the intermediary level. (Contains 1 table.)