This study, using student ratings of lecturers, examines the perceived effect of the lecturers ability to communicate effectively. The relationship between the standard question -- "The lecturer was able to communicate ideas and information clearly" -- and the global rating question -- "Overall, the lecturer is an effective teacher" -- was investigated in 7072 undergraduate standard teaching surveys from one university, using the lecturer's language background as a factor. The results show that overall student ratings of English as a second language (ESL) lecturers are, on average, 0.4 points lower on a fivepoint scale than student ratings of native English speaking lecturers. There is a strong interaction between this average difference and the lecturer's faculty, with little difference in arts (humanities and social sciences) through to 0.6 points difference in science. The study also found that, of the four categorical questions used in the universitys standard teaching survey, the "communication" question had the highest correlation with the "overall" question. The correlation (R=0.96) suggests that the standard teaching survey is overly influenced by the students' perception of this one aspect of teaching -- reflecting a transmission model. The rating difference between ESL and native English speaking lecturers is briefly explored. In addition, the paper briefly considers the implications of the above findings for teacher development and for student expectations against a background of a growing ESL student population.