The present paper is based a systematic research reviews (Hirsh & Lindberg, forthcoming) for the Swedish Research Council, aiming at systematically identify and report recent and current trends in research into formative assessment, in Sweden as well as internationally. Here the issue is to illuminate firstly, in what ways formative assessment is perceived and used in research contexts, and secondly what differences and similarities that exist in research on formative assessment between countries. The review is limited to research published in Swedish and peer-reviewed articles in English during 2000 - 2014. The initial searches yielded approximately 2000 hits (internationally published articles) and 230 Swedish theses and articles. However, most of the hits were related to other than compulsory school and were therefore excluded. Overall findings are that the term 'formative assessment' is used in either a narrow (instrumental) or a broad sense (a complex phenomenon addressed on various levels); that Asian studies tend to be related to ICT, while British and Australian studies have a larger width and American studies tend to be related to accountability or the No Child Left Behind-reform. In Swedish research, young researchers and classroom studies dominate. To conclude: not only theories of learning, but also basic epistemological and ontological assumptions need to be addressed in future research, as do issues related to assessment embedded in teaching, which calls for collaboration with research into classroom practices.