A study was conducted in 1980-81 at Santa Ana College (SAC) to collect data on the English communication skills of non-native English speakers and to determine if a relationship existed between these skills and student's educational success. A sample of 22 classes, with an enrollment of at least 50% non-native English speakers and representing a variety of disciplines and instructional methods, was selected. The Nelson-Denny vocabulary and comprehension tests and the Comprehensive English Language Test (CELT) of listening were used to measure English ability. Study findings, based on test scores and grades of 53% of all students enrolled in the sample classes at census week (N=503), included the following: (1) Vietnamese and Spanish were the most commonly spoken non-English languages; (2) overall, fewer A's and more B's, C's, and D's were earned in the sample classes than at SAC as a whole, however, these classes had lower withdrawal rates; (3) Anthropology 101 and Sociology 100 showed significant positive correlations between test scores and grades, while Chemistry 219, Math 180, and Music 161 showed consistently negative coefficients; (4) as a whole the grades of English and non-native English speakers were comparable; and (5) success rates tended to favor students who had completed English courses. The study report discusses methodology, statistical findings, and limitations and is appended by statistical data tables. (KL)