Past research has found that many pre-university L2 learners, having completed an Intensive English Program (IEP) still have difficulty in undertaking various disciplines in English-speaking tertiary institutions and continue to exhibit numerous linguistic problems (Bialystok, 2001, Celce Murcia 2001). The purpose of this paper is to present the findings on the investigation of L2 learners' English proficiency in reading, writing, grammar, listening and speaking upon their completion of an Intensive English (IE) program using their IELTS (Academic), in-house exams and English Placement Tests (EPT) scores, and the efficacy of IE program. IELTS test is chosen for this study due to its increasing popularity in Malaysia and its internationally recognised value and quality. The study was conducted in two parts. In Part One, all 72 Level 4 IE students were given an in-house EPT (English Placement Test) pre-test on their entry and another EPT post-test on their exit, and then their pre-test and post-test results were compared. In Part Two, 22 volunteers sat the IELTS test at the end of the program. The IELTS results of the 22 volunteers were compared with those who did not. Data were analyzed using both quantitative and qualitative methods. This paper hopes to shed some light on (i) whether or not L2 learners' English language proficiency can be significantly enhanced and influenced by an intensive English program and (ii) how leaners' perception of their own learning strategies influence their learning progress.