The paper evaluated the impact of Ins-Service Training Programmes on Job Performance of Academic Staff of Colleges of Education in the 21st Century. This is against the outcry of members of the public on the quality of graduates from primary – tertiary levels. A survey approached was employed for the study, one Hypothesis was proposed and tested. The findings reveal that In-Service Training Programmes significantly improves staff job performance in many areas of their duties such learning news strategies for teaching managing large class size, improving their knowledge base in the subjects among others. It was therefore suggested among others that employers and their management need to provide within the framework of agreed policies, a wide range of development opportunities for all categories of staff.