This article demonstrates some enlightenment the author has gained from the brilliant expositions by Prof.Lu Siyuan and Prof.Cai Jigang and presents the following pros and cons about the concept of ESP:The word specific refers to purposes rather than English;ESP is a linguistic course instead of a specialized course;ESP aims mainly at developing the student's skills for specialized studies and high-level communication and not those merely for daily social communication;ESP course should be the replacement for the existing College English course rather than its extension;the compilation of ESP textbooks lays special emphasis on authenticity instead of sequential gradualness;the ESP teacher should play multiple roles and not the only role as instructor.