Universal Design for Learning is reaching more and more classrooms every day. Teachers and students are excited about this new framework of curriculum development that offers options for how content is presented; options for how students demonstrate what they have learned; and options for engagement. But how do we measure UDL? Numerous tools exist to measure various aspects of UDL (e.g., self-efficacy with UDL, educator and student perceptions of UDL, general UDL knowledge, and UDL lesson planning). However, only a handful address whether UDL is actually implemented in a learning environment. Join us to discuss existing tools that measure UDL implementation, how UDL could be/should be measured, and what researchers and practitioners would like to see in a UDL implementation tool.