In an effort to fill a perceived gap in research concerning the relationship between cultural knowledge and second language proficiency, a study was undertaken with foreign students of English as a Second Language (ESL). The subjects were 30 college juniors in a variety of disciplines taking an English world literature class. Subjects were administered a 50-item multiple choice test on general knowledge about American culture that focused on values, customs, media, politics, arts, and economy. The test was validated with American students. A week after taking the test, the subjects were administered a standardized written test of English proficiency and oral proficiency was measured. Results indicate a strong correlation between cultural knowledge, written proficiency, and oral skills. Since none of the students had taken a course in American culture, it is assumed that cultural and linguistic knowledge were acquired simultaneously. Variability in the correlations for each student was not found to be related to length of stay in the United States, nationality, or college major, but was statistically related to exposure to mass media, both print and visual/aural. It is concluded that media exposure may help develop both second language skills and target cultural knowledge. Contains seven references. (MSE)