This article focuses on assessing the performance of government secondary school headteachers in the context of heads' leadership qualities, instructional behavior, capabilities of interpersonal relationships, professional attitude and managerial abilities. The small-scale survey was carried out in 2006 in district Mianwali, Pakistan. The sample comprised 150 secondary school teachers drawn at random from 15 government schools. Data was collected through a questionnaire comprising 38 items on a five-point rating scale on various aspects of headteacher performance. The instrument was validated through a pilot study and its reliability was established at 0.901 (Cronbach's alpha). Results revealed that the performance indicators of professional attitude, interpersonal relationship, leadership qualities and managerial abilities were found to be better, but the aspect of instructional behavior was weaker among the headteachers. The performance of female headteachers in regard to instructional behavior, professional attitude and managerial abilities was found to be relatively better than those of their male counterparts. There were significant intercorrelations among all the independent variables of headteacher performance. (Contains 5 tables.)