Knowing Head Start teachers' existing beliefs can help to tailor the professional development they receive on topics surrounding dual language learners (DLLs) development and best practices. Teachers who have access to accurate information that strengthens best practices and dispels their misconceptions related to DLLs may be better equipped to provide a quality preschool experience to DLLs in their classrooms. Twenty-three female teachers working in Head Start preschool centers were interviewed on their beliefs regarding DLLs, their development, and instructional practices for DLLs. Modified consensual qualitative analysis was completed as an inductive, multi-step analysis process to summarize the beliefs of the participating teachers. Six major themes emerged. These themes included: (1) definition of DLL; (2) value of DLLs' home culture and language; (3) ease of learning English; (4) primary classroom language; (5) home language use in the classroom; and, (6) language difference versus language delay or disorder. Implications and recommendations for professional development are discussed. (author abstract)