This presentation will attempt to provide a framework through which cognitive diagnostic assessment can be located in relation to other assessment agendas. Although interest in formative assessment has grown recently, what constitutes formative assessment remains contested. Indeed, many researchers have pointed to the need for a theory of formative assessment that placed teaching and learning at the centre and for the application of modern psychometric models. Formative approaches to assessment that aim to enhance students’ engagement in learning have occurred through assessment-centred learning, self- and peer-assessment (with a focus on self-regulation of learning), and through attention to feedback. The emergence of comprehensive models of assessment informed by cognitive science accompanied by the application of modern measurement models (specifically the Rasch model and its embellishments), has enabled scientific approaches to formative assessment. Conventional models of diagnostic assessment are normative. By contrast, cognitive diagnostic assessment embodies a model of learning that recognises the paths (trajectories or progressions) that students take in their learning. The application of measurement models enables at least the validation of students’ empirical learning paths but can do more than this. Cognitive diagnostic assessment takes formative assessment in a new direction informed by learning science.