Part of a study of the oral communication skills of Chinese scientists in an intensive course in English for science and technology focused on the importance of attaining accuracy or mastery for their specific language needs and the error tolerance level of English-speaking scientist peers. Three students in each of three different science specialties at the Graduate School English Language Center in Beijing were chosen as subjects for speech samples of two types: one a planned presentation as in a formal, professional setting; the other, unplanned, informal conversation. The three students in each specialty had language skills considered good, average, and weak. Native English-speaking scientists and English teachers evaluated the taped speech samples. Results suggest that the Chinese scientists probably could function adequately in formal and informal professional settings and have adequate speech speed, but with only acceptable grammar. It is also concluded that the program had successfully lowered the psychological barrier about making mistakes in English. Adjustment of language programs' expectations of accuracy and fluency to meet the real language needs of the students, weighing grammatical accuracy against other factors such as word choice and pronunciation, is recommended. Appendices consist of the evaluation questionnaire and two statistical tables showing results. (MSE)