Assessment takes center stage for a wide array of stakeholders worldwide. Understanding and making informed choices about students’ literacy achievements and their teachers’ teaching competence in the 21st century entails a consideration of multiple pieces that hold individual and collective importance. Some hold longstanding and traditional significance. Others stem from [Page 43]the ever-expanding understanding of literacy and the advances triggered by newer technologies. This entry discusses how literacy can be evaluated using formative and summative assessment and the need for test reliability and validity. It then looks at how teacher assessment can be combined with student assessment, and the changes in assessment that are accompanying the introduction of the Common Core State Standards.