The Communicative Approach in language teaching originates from a theory of language as communication. According to this approach, the main objective of language teaching is to develop what Hymes (1972) referred to as "communicative competence". The literature on language teaching suggests that EFL teachers' attitudes and practice toward communicative language teaching (CLT) vary depending on how they conceptualize CLT. Thus, the purpose of this study is, firstly, to explore high school and institute teachers' attitudes toward the CLT within the context of an expanding circle, Iran. Secondly, the study aims at exploring the extent to which the teachers of these two contexts materialize and substantiate their attitudes. To fulfill the objectives, a questionnaire consisting of five main factors was administered to 100 male and female explore high school and institute teachers. Moreover, a classroom observation scheme, designed on the basis of literature on CLT, was used to monitor how well and to what extent teachers practice what they believe. Descriptive and inferential analysis of the data indicated that high school and institute teachers' attitudes toward the CLT are positive, indicating a welcoming atmosphere toward the implementation of CLT. However, among the participants only the teachers of institutes practice a quasi-CLT type of approach in their classes.