This analytical report seeks to address the evident gap in the formative assessment of social and emotional education by providing a framework indicating how social and emotional education may be assessed through a whole-school approach, both at individual (learner) and contextual (classroom climate and whole school system) levels, accompanied by illustrations of how this may be carried out in schools. It presents a framework of guiding principles for the formative assessment of social and emotional education within the EU, and provides various tools that may be used to formatively assess social and emotional education at the levels of the individual learner, classroom climate and whole-school system. The report also identifies a number of areas that need to be addressed in order to advance the effective implementation of the formative assessment of social and emotional education in the EU. This report should serve as a platform for the development of a formative, collaborative, systemic and inclusive European identity for SEE assessment, in contrast with other individualistic, personality- and character-based, and normative modes of assessment. It also provides a more integrated framework for the assessment of SEE in the EU and helps to bring greater consistency to assessment practices for this key competence at regional, national and European levels.