The teachers are dynamic force of education system. Policy makers, district and school leaders, parents, all are increasingly concerned about the improvement of the quality of education. Effectiveness in learning and sound foundation of an educated society can be possible by the committed role of teachers. So, availability of effective teachers in making an efficient education system is a prerequisite. Teachers? education and training programs are being offered by different institutions in Pakistan. The purpose of these trainings is to develop teachers who are professionally competent. Quaid-e-Azam Academy for Education Development provides in-service training for public sector school teachers to enhance their professional competence. This study was conducted to evaluate the impacts of continuous professional development programs conducted by Quaid-e-Azam Academy for Educational Development (QAED) on the professional skills of secondary school teachers. The population of the study comprised of secondary classes? teachers of high schools of district Gujranwala. A sample of 200 teachers, 150 teachers for questionnaire (75 trained and 75 untrained) and 50 teachers for observation (25 trained and 25 untrained), was selected from government high schools through convenient sampling techniques. Twenty-five head teachers were also selected for questionnaire through convenience sampling techniques from government high schools. Data was collected through personal observation and questionnaire. Descriptive statistics such as means and inferential statistics such as Chi Square were used to describe the data. It was concluded that there was a significant association between the training and performance of secondary school teachers. The teachers who received in-service training through QAED were found more effective in their performance. It is suggested that in-service training must be arranged for all the teachers to prepare skilled teachers to improve students? performance. To get maximum output from in service trainings, there should be proper monitoring system by higher authorities.