The Twenty-third Session of the Intergovernmental Meeting on the Acid Deposition Monitoring Network in East Asia (IG23) was convened virtually from 24 to 25 November 2021 to make important decisions on the expansion of the scope of the EANET, among other topics. The event gathered over 70 representatives of the EANET participating countries, namely, Cambodia, China, Indonesia, Japan, Lao PDR, Malaysia, Mongolia, Myanmar, Philippines, Republic of Korea, Russia, Thailand and Vietnam, the Secretariat, and Network Center for the EANET.