This study focused on the attitudes that elementary teachers have toward their English language learner (ELL) students' native languages (e.g., Spanish) and their use in instruction. A 27-item Likert-scale survey was administered to 152 first- through fourth-grade teachers from five school districts in Maricopa County, Arizona. These school districts have a large number of schools with students learning English as a second language. The researchers found that teachers' attitudes toward their ELL students differ significantly with the type of certification or endorsement they hold. The bilingual-certified teachers were more supportive of their ELL students using their native language in the classroom than were traditional and English as a Second Language-certified teachers. In contrast to previous studies, the researchers found that the more years a teacher taught, the more his or her attitude became negative toward his or her students' native language. Implications for training of bilingual teachers are discussed. (Contains 6 tables.)