Teachers' online discussion forums play an important role in ESL teachers' professional development. They provide opportunities for in-depth peer-to peer interaction, self-directed learning, exchange of knowledge and expertise, and greater involvement in teaching-learning and student-teacher issues. Forum members can share resources such as tests, e-books, lesson plans and software. They post questions and receive answers about teaching and learning English issues. Forums also enhance teachers' awareness of non-conventional issues such as: Teaching business with no teaching certificate, Facebook pen-friends, teaching in rural schools in China, online tutoring, using Taekwondo to teach English, testing private students at Euro levels, using songs in TEFL, stopping parrot training, teaching pre-literate students and others. The presentation will give examples of online discussion forums for ESL teachers, kinds of topics, issues and problems posted about the teaching and learning of English, and their role in ESL teachers' professional development as perceived by teacher members. [Paper presented at the ELTAM-IATEFL-TESOL International Biannual Conference (7th, Skopje, Macedonia, Oct 2012).]