Xiufeng Liu is Associate Professor of Science Education at the State University of New York at Buffalo. He received his doctorate in science education from the University of British Columbia in 1993. He was a high school chemistry teacher in China, a research associate at the China National Institute for Educational Research (CNIE), and a science teacher educator in Canada before his current position. He conducts research in the closely related areas of technology-enhanced science assessment, applications of measurement models in science education, conceptual change in science, and science curriculum policies. He has published over 30 refereed articles in key science education journals, 5 books, 15 book chapters, and presented numerous papers at national and international conferences. Dr. Liu teaches courses entitled Measurement and Evaluation of Science Teaching, Seminar on Science Teaching, Seminar on Science Curricula, and Technology for Science Teaching. In addition, he conducts an annual summer science assessment workshop for teachers, and is frequently invited to give talks and workshops on science assessment including Rasch measurement.