Many of the most important questions studied in astronomy touch on fundamental issues with great popular appeal, e.g.: How was the world created? How did life arise? Are
we alone? How does it all end? Communication of astronomy to the public is important and will play an ever-greater role in the coming years. The communication of achieved results is now seen frequently as a natural and mandatmy activity to inform the public, attract funding, and recruit science students. In some countries, university statutes are even being rewritten to include communication with the public as a third mandatory function, complementing research and education. The three parts of this essay address the many exciting communication
developments that have recently taken place within the International Astronomical Union. Section 25.1 contains a general introduction to the recent science communication
initiatives from the IAU. Section 25.2 briefly reviews the essential elements of a communications office and strategy, based on the lessons learned at the European Space Agency's Hubble Space Telescope EPO (Education and Public Outreach) office in Munich. Section 25.3
discusses the particular communication of the planet definition debate that took place at the 2006 IAU General Assembly while our Special Session was in progress.