This study investigated the relationship of out-of-class English use and proficiency gains. It also explored the relationship of gender, proficiency level and native language and the possible effect of these demographics on out-of-class English use and language gains in English. Though some studies have shown that those who spend more out-of-class time using the target language have higher language gain (Seliger, 1977), other studies have not found this to be true (Day, 1985; Freed 1990; Spada, 1986). Some reasons for the discrepancy in findings may be differences in the length of the time data is collected, samples of study participants and types of tests used to measure proficiency. Sixty-one students at an intensive English language program came from 12 different language backgrounds and 4 proficiency levels. They participated in a 31-week-long study. Participants took a proficiency pre- and posttest (Elicited Imitation Test) and responded to a questionnaire designed to elicit information about out-of-class language use (Language Contact Profile). In addition to the questionnaire, six students participated in semi-structured interviews that offered additional support for the data gathered by the questionnaire. Data obtained from the questionnaire and interviews was compared to gains in proficiency between the pre- and posttest. The results suggest that using English out-of-class helps improve oral proficiency. In addition, the study shows that gender, proficiency level and native language are not significant predictors of out-of-class English use and proficiency gains. These findings are discussed in light of what teachers and school administrators can do to help their students use the target language in and out of class for best results.