This research paper extrapolates the perceptions of English Language teachers about the effectiveness of the newly introduced Individual Plan Measurement System (IPMS) in terms of task performance at the University of Technology and Applied Sciences, Al Musannah (UTASA), Oman, and how this new performance appraisal system has contributed to teachers' professional development. For the current study, the researchers employed a mixed methods approach by administering a survey questionnaire among the ESL teachers (N=31) of UTASA, conducting a semi-structured interview with selected staff members (N=7), and analyzing the data related to professional development activities conducted before and after the implementation of the new appraisal system. The study shows that most UTAS-A ELC staff perceive that IPMS has helped them plan and execute their professional goals effectively. Furthermore, the findings of the study highlight that a timebound individual plan guided and monitored by institutional agencies has a positive effect on employees' intrinsic motivation and professional development, and it can make their task performance more efficient and systematic.