The 2015 Gordon Research Conference on Visualization in Science and Education will continue a tradition of bringing together diverse communities of persons engaged in the production, study and application of visualizations to enhance and promote scientific understanding. The over-arching theme for the 2015 conference is "Grand Challenges in the Use of Visualization in Science and Education". This will be achieved through the exploration of the following seven sub-themes which help define the plenary sessions for the 2015 GRC: What Technical Limits/Challenges Remain in Scientific Visualization? What are the big technical challenges that limit scientific visualization? This session will explore the cutting-edge of research and practice in this area. How Do We Best Integrate Visualization in Education? Visualizations have long been a tool used to communicate between scientists. Educators are incorporating more and more visualizations in a variety of learning experiences. What best practices have emerged and how can those practices inform the producers of visualization? The dialogue between visualization producers and consumers has been a regular staple of this conference and in this session, we’ll continue to explore this question. What Are the Special Challenges in Visualizing Large Datasets ("Big Data")? Datasets are becoming ever larger in a variety of scientific fields. What are the key techniques and challenges to visualizing these? We’ll discuss the impact of big data on visualization as well as how visualization is a necessity in analyzing big data. How Do We Assess the Impact of Visualization and How Does Visualization Allow New Modes of Assessment? Assessment lies at the heart of determining the effectiveness of visualizations and is an opportunity to engage a cross-disciplinary community in learning if, and to what extent, visualizations are effective. Moreover, visualizations enable ways of knowledge assessment that move beyond traditional means. What Are the Best Practices in Communication Using Visualizations? Visualization is now a commonplace communication tool. What is known about the best practices of communicating within communities of practice and with the general public? What Do Student-Created Visualizations Reveal About Student Understanding? The creation of a visualization is a powerful act. Student created visualizations not only reveal a great deal about students’ reasoning and content knowledge, but also support learning and reasoning processes. What Principles Guide Artistic vs. Scientific Visualization? Artists and scientists develop visualizations with different goals. What about when artists are developing visualizations to communicate science? In this session, we’ll explore the intersection of art and science to develop a common understanding of creating visualizations that are aesthetically pleasing and effective for both learning and scientific reasoning. What Are the Latest Advances in Visualizations? New technologies continually add new tools and possibilities for the use of visualization by scientists and educators. This session will introduce cutting-edge applications that are transforming visualizations in different areas. We’ll discuss the advantages and challenges of these new approaches and anticipate future applications. What Does the Future Hold for Visualization in Science Education? Anticipating as yet unknown tools and technologies is an important grand challenge in the use of visualization. This session will ask experts to forecast the use of visualization in new areas and the possibilities that are on the horizon. A robust discussion will makes this a fitting final session for the conference. In addition to the list of sessions described above, a vibrant and engaging week of posters and discussion will help ensure that the 2015 Gordon Conference on Visualization in Science and Education will be a stimulating and engaging conference! For more information, please visit the conference chairs’ web site.