A study investigated whether proficient non-native speakers of English teaching English as a foreign language (EFL) modify their speech when addressing less proficient students, as has been observed among native teachers of English as a Second Language. Fourteen Peruvian teachers' classroom interactions were recorded. Comparisons were drawn between the levels of syntactic complexity in classroom and interview contexts and among three instructional levels. Minimal terminable units (T-units) were used to measure syntactic complexity. Results reveal that the speech directed to learners in the classroom was significantly less complex than the speech the teachers were capable of producing in another setting. Speech used at the highest and lowest levels of instruction was found to be significantly different in complexity. Implications and research limitations are discussed. A 14-item bibliography is included. (MSE)