English language is now almost a necessary requirement for both development and international communication in many countries, learning it is a useful tool among ordinary people, scientists, institutions and governments. While searching for the reasons behind such growth of interests towards learning English, one may find different answers, as well as different motives. In this sense, with the growing number of universities all around the country demand for English teachers has exceeded supply. To cope with the situation, a vast majority of teachers who have been prepared to teach General English are asked to teach ESP. Hence, once they get a position as English teachers they hold the statue of EFL teachers; this is mainly due to the fact that during their training, they had no ESP teaching methodology. Therefore, one may say that an ESP teacher is originally a General English teacher who is recruited to teach ESP courses, and by which he can apply for positions in different departments including the English department. All problems stemming from the questions as to what to teach and how to teach it apply both to teaching General English and teaching Special English. The difference is probably in the degree of problematicity. With ESP, these two questions are further complicated. The choice of content relevant to the purposes of learning becomes more difficult to make, partly because language teachers usually do not possess inside knowledge of the profession or science in which the language learners will function as second language users.