This study reports the perceptions and understanding of extensive reading (ER) of 259 ER practitioners in Japan, Thailand, Mongolia, and Vietnam. The majority of participants understood the core principles of ER, namely (a) the fluent reading of (b) a lot of (c) easy texts. However, about 25% of the participants in Thailand, Mongolia, and Vietnam did not understand that the texts need to be easy and read fluently. Despite all the participants being self-declared ER practitioners, a large number of participants in Mongolia, Thailand and Vietnam often reported the desire for intensive reading practices in their ER classes. This suggests more training on ER is necessary. Participants highly rated all questions regarding the need for more ER training, showing that even the more experienced ER practitioners still need assistance. [Note: The volume number (36) shown on the footer of the PDF is incorrect. The correct volume number is 37.]