The purpose of this study is to assess the effectiveness of an intermediate textbook titled &ldquo / New Bridge to Success 3&rdquo / , which was prepared by Ministry of National Education as an instructional material for the ninth grade high school students from the perspectives of the teachers and students. The evaluation of the textbook concerned was conducted at macro level on the basis of eleven criteria. Both quantitative and qualitative data were obtained through student questionnaires administered to 336 students and interviews with eight teachers. Frequencies, percentages, means and standard deviations were calculated for each item to describe the overall picture of how the students rated the textbook in terms of ten criteria. Data collected through interviews were transcribed, content- analyzed and grouped according to 11 criteria used in this study for the evaluation of the particular textbook The results revealed that both teachers and students felt negative about the most of the characteristics of the textbook. It was found that the reading passages needed to be simplified in terms of both vocabulary load and structures. Majority of the students and all the teachers mentioned that the level of the textbook was not appropriate for the particular age group. It also indicated that the materials failed to consider learning style preferences of the visual, auditory, and kinesthetic learner. On the other hand, one of the strengths of the textbook was the artwork&rsquo / s being up-to date and helpful for the students to understand the lesson