The 17th World Lake Conference will be hosted by the International Lake Environment Committee (ILEC) and the Ibaraki Prefectural Government. The theme of this global-scale conference is “Harmonious Coexistence of Humans and Lakes – Toward Sustainable Ecosystem Services.” To be held in English, the conference will include technical sessions on a range of topics related to lake, reservoir, wetland and lentic water systems and their ecosystem services, including their scientific and management implications, prominent keynote speakers, field trip to Lake Kasumigaura (second largest lake in Japan), international policy forum, poster session, exhibition, banquet, cultural events, awarding of Kasumigaura prize, and preparation of Ibaraki Declaration. The call for abstracts is extended to May 10, 2018. Further information is available on the conference website (http://www.wlc17ibaraki.jp/en/index.html).