Teacher Discussion Forums

Being new to the ESL field, I have just learned about bilingual classrooms. There aren't many schools in my area that have bilingual classrooms and I find it very interesting. What are the benefits for ELL's in bilingual classroom compared to regular ESL ones where they only learn in English. I think that it would be more overwhelming for a beginner ELL to learn in English only. I also think that bilingual classrooms may hinder a students learning of the English language. I'd like to know the pros and cons of Bilingual Classroom in comparison to English-only ones.