This paper considers alternative assessment, feedback and cybernetics. For more than 30 years, debates about the bi-polarity of formative and summative assessment have served as surrogates for discussions about the workings of the mind, the social implications of assessment and, as important, the role of instruction in the advancement of learning. Currently, alternative assessment lives uneasily with its classical counterpart. Classical test theory--and its conception of the summative value of the true score --came from behaviourist learning theories developed in the first three decades of the twentieth century. Formative assessment, with its conceptions of feedback and development , had a different origin. It arose from cognitive and constructivist theories of learning that emerged in the 1930s and 1940s. This paper identifies the tensions that underpin this uneasy coexistence. It suggests that different conceptions of mind lie behind these tensions and, to mark the autonomy and integrity of formative assessment, it offers an alternative, univalent descriptor: "constructivist assessment".