Non-cognitive outcome measurement is more challenging to assess than cognitive because of its highly diverse dimensions and difficulties in sampling performance on these dimensions. This chapter addresses the highly incomplete knowledge base on the potential importance of non-cognitive aspects of students and schools, issues of measurement and assessment, and their predictive value on adult outcomes. From βThe Role of International Large-Scale Assessments: Perspectives from Technology, Economy, and Educational Research,β copyright Springer Science+Business Media Dordrecht 2012.