This study looks at Student Teams-Achievement Division (STAD) implementation from a qualitative approach by observing and interviewing a teacher who successfully improved his EFL students' reading achievement with this technique. The procedures by Shaaban and Ghaith (2005) were the foundation for STAD implementation, and an interview was done to exhibit the teacher's stance on the use of STAD. Based on our observation during his teaching in a reading class by implementing STAD, it was found that he did not implement one procedure of this technique, which was assigning a role for each member of the groups. From the interview, he informed that he did not conduct this procedure because he believed that assigning roles should be entrusted to the students to increase their sense of responsibility towards the accomplishment of the group task. Furthermore, he also modified five procedures from nine procedures of STAD proposed by Shaaban and Ghaith (2005). The modified procedures were related to the way the quiz was given to students, providing printed answer key, ways of correcting the student's quiz, providing the team recognition form, and ways of recognizing the students' achievement. He informed that they were modified due to the efficacy of students, time limitation and the school's financial problem.