Universal design principles address policies and practices that are intended to improve access to learning and assessments for all students. Universal design principles are important to the development and review of assessments because some assessment designs pose barriers that bar students with disabilities from showing what they know. Universal design techniques can result in more accurate understanding of what students know and can do. Universal design of assessments is different from accommodations because accommodations require authorization from Individualized Education Plan (IEP) teams. Universal design techniques can be applied from the beginning of test development to the point when students engage in assessments. Universally designed general assessments may reduce the need for alternate assessments, and may provide states with more cost-effective assessments. Further, tests designed with universal design principles can provide educators with more valid inferences about the achievement levels of students with disabilities, as well as the achievement of their peers without disabilities. Universal design elements and procedures are undergoing continued explication and research.