The purpose of this study was to explore the factors influencing the beliefs middle school mathematics teachers have about English Language Learners (ELLs) in mainstream classrooms. One hundred forty-nine middle school mathematics teachers from 11 school systems in Georgia completed the "Middle School Mathematics Teachers' Beliefs about English Language Learners Questionnaire." Teachers who had received training felt significantly more prepared to teach ELLs and to help them understand class materials than did teachers who had not received training. In addition, females believed significantly more than males that teachers should modify assignments for ELLs. Teachers need more training in ELL pedagogy to successfully meet the needs of the ELLs they are likely to encounter. (Contains 3 tables.)