International Large-scale Student Assessments are the most prominent example of internationalization processes in education. A number of studies have analysed the policy reactions to such studies, particularly to the Organisation for Economic Co-operation and Development (OECD) Programme for International Student Assessment (PISA) study. PISA and comparable projects have also raised concerns of a feared increase of assessments and accountability procedures. So far, systematic empirical evidence that could corroborate such concerns has been scarce. In this paper, we examine the prevalence of assessment and accountability practices at secondary education level as well as changes in these practices over time. We explicitly focus on changes over time by drawing on data from PISA 2000 to PISA 2015. Analyses over time are not straightforward with PISA, as the questionnaires change between survey rounds. This leads to different coverage of specific indicators over time. We present descriptive analyses for 20 OECD countries. The results show an increasing trend for the vast majority of the generated indicators, indicating that assessments and the use of assessments for purposes of accountability increased within the larger part of the OECD during the last 15 years. Likewise, more horizontal, peer-oriented evaluation procedures focusing on organizational learning gained importance. A cluster analysis based on selected indicators of 2015 revealed that there are four distinct groups of countries, which are mainly distinguished by different levels of the prevalence of assessment, accountability and evaluation practices.