The book examined the impact of teachers' communication proficiency on students' academic performance. Five primary levels of communication proficiency are identified among the teachers in most secondary schools, with the Advanced level rated highest, followed by the superior level, then distinguished level, Intermediate level and Novice level, which is the least. It was discovered that teachers' communication proficiency has an impact on the academic performance of most senior secondary school students, with no significant difference in the level of academic performance of male and female students and a negative correlation in the level of senior secondary students' academic performance and the level of teachers' communication proficiency in most secondary schools. The factors influencing teachers' communication proficiency in the secondary school were: poor/negative motivation, teachers' teaching experience, teachers' training and qualification, too much workload, and long working hours for teachers. Unavailability of resources and instructional materials, general infrastructure condition, poor and inadequate teachers' Pay/Salary, political interference and instability.