Assessments can be considered to be an integrated part of formal educational settings, in different forms and used for different purposes. In this contribution we will discuss and analyse the use of assessments in comprehensive school in Scandinavian countries through time, as we will include different kinds of documentary and empirical studies in the argumentation. We will focus on which kinds of assessments has been used, for which purposes and the role of this in the perspective of society. More contemporary trends will be discussed, specially the use of standardised testing. Scandinavian countries differ at some points concerning the use of assessments of this character. Assessments points to and creates differences between pupils and play a key role in processes of socialisation, marginalisation and in- and exclusion in society, as discussed by theorists such as Bourdieu and Bernstein. If the comprehensive school is based on the general idea of a school for all, how can different ways of practising assessment support or work against this idea? What conclusions can be drawn from the experiences in the Scandinavian countries?