This article presents a description of the proficiency level of a group of English teachers who participated in the study about the conditions of implementation of the National Bilingual Program in Santiago de Cali. To offer a view of teachers’ proficiency beyond tests results, and in an effort to understand the make-up of this proficiency, focus group interviews and survey data were also used. Findings were analyzed following the models of teacher development of Richards (1998) and Roberts (1998), as well as theory about language proficiency from different authors. The results show that teachers from both public and private sectors are still in the process of building the proficiency levels sought by the Ministry of Education. The study also found that the elementary level, especially in the public sector, provides a frail basis for teaching and learning English at the secondary level.