This study investigated the language learning strategy use of 55 ESL students with differing cultural and linguistic backgrounds enrolled in a college Intensive English Program (IEP). The IEP is a language learning institute for pre-admissions university ESL students, and is an important step in developing not only students' basic Interpersonal Communications Skills (BICS), but more importantly their Cognitive Academic Language Proficiency (CALP). Proficiency with academic English is a key contributor to students' success in learning in their second language. Using the Strategy Inventory for Language Learning (SILL), the study examines the relationship between language learning strategy use and second language proficiency, focusing on differences in strategy use across gender and nationality. The study found a curvilinear relationship between strategy use and English proficiency, revealing that students in the intermediate level reported more use of learning strategies than beginning and advanced levels. More strategic language learners advance along the proficiency continuum faster than less strategic ones. The study found that the students preferred to use metacognitive strategies most, whereas they showed the least use of affective and memory strategies. Females tended to use affective and social strategies more frequently than males. Conclusions and pedagogical implications of the findings are discussed. (Contains 6 tables.)