However, few studies investigated the working states of NESTs and NNESTs at Intensive English Programs (IEP) and the distinctive components that affect their successes and challenges. Lucie M. Moussu (2006) researched this project thus investigates 1040 ESL students’ attitudes towards NESTs and NNESTs, the variables (students’ first languages, gender, class subject, level, and expected grade, as well as teachers’ native languages) that influenced students’ responses, and the effects of time on students’ attitudes, with questionnaires completed both at the beginning and at the end of the fall 2005 semester. Online questionnaires additionally requested 18 NNESTs and 78 NESTs’ self-perceptions about capability and teaching skills, as well as 21 IEP administrators’ beliefs about, and encounters with NNESTs and NESTs. Results showed that in general, students’ attitudes were more positive towards NESTs than towards NNESTs, in spite of the fact that students taught by NNESTs held a significantly more positive attitude towards NNESTs in general than students taught by NESTs. Positive attitude towards NESTs and NNESTs increased significantly with time and exposure.