Dr. Tiffany Timbers is an Option Co-Director of the UBC Master of Data Science program, and is a committed proponent for developing and using open textbooks in her courses. She has authored or co-authored two open textbooks that are released under the Creative Commons license: Introduction to Data Science and Python Packages. Dr. Timbers has also advocated for the open release of syllabi for all Master of Data Science courses, along with lecture notes and labs for many other courses, which she makes freely available on GitHub under a CC-BY-SA license. Overall, this is a tremendous effort and shows a sustained dedication to OER.