In an effort to determine why students with similar academic abilities have differing rates of success in learning English as a second language (ESL), a study of 225 native speakers of Spanish enrolled in the ESL program at Manhattan Community College was conducted during the 1975 Fall semester to test the hypothesis that success in ESL is dependent upon the individual's instrumental and integrative motivation and upon his/her fear of losing cultural and linguistic identity. Using a bilingual questionnaire, responses to 36 predictor variables, including attitude and motivation measures adapted from Gardner and Lambert, were evaluated and correlated with test results in oral proficiency, passive grammar, and essay writing. Results show that only two predictors were statistically significant at the .05 level: "anomie," which had a positive correlation to oral proficiency, and "father's knowledge of Spanish," which had a negative correlation to progress in passive grammar. The study report concludes with a discussion of the possible reasons for the low correlation rates. A sample questionnaire, six tables describing the statistical correlation of the predictor variables with the progress criteria, and excerpts from the ESL curriculum at Manhattan Community College are appended. (JP)