Polar Data Forum II will build on successes of the first International Polar Data Forum in October 2013 in Tokyo, Japan that—alongside other international and national meetings—identified priority themes and key challenges in the domain of polar data management (Polar Data Forum Communiqué). The Second Polar Data Forum will further refine these themes and priorities, and will accelerate progress by establishing clear actions to address the target issues, including meeting the needs of society and science through promotion of open data and effective data stewardship, establishing sharing and interoperability of data at a variety of levels, developing trusted data management systems, and ensuring long-term data preservation. The Forum will be held in conjunction with the scheduled annual meetings of both the Arctic Data Committee of the International Arctic Science Committee and Sustaining Arctic Observing Networks and the Standing Committee on Antarctic Data Management of the Scientific Committee on Antarctic Research (SCAR), effectively creating a Polar Data Week.