I am going to take it is common ground that we value art and design and don't think it is a fraudulent practice - or at least not more often fraudulent than other activities. Yet at the same time we have deep anxieties about how far the practices and products of art and design could in principle be proper topics of assessment. So we have a set of dilemmas. Either we genuinely do value what we say we do, in which case there must be some shareable criteria of what is valuable in what we value, hence a basis for assessment. But the concepts of assessment that we seem to be faced with seem both dubious and hard to replace. Yet, if we doubt the possibility of assessment should we not equally doubt whether do we in fact value what we think we do?Concepts of "judgement" (or "criticism") come in bitter and sweet flavours: tolerant or liberal people are asked not to be judgmental or over critical. We have good reason to fear the sorts of judgements and criticism that cramps our liberty to be to think for ourselves, not to have alien values (values alien to us, that is) imposed on us. And this, we rightly feel, is something we should value most in the arts. If we judge the arts we are not magistrates, and should avoid the magisterial. But there is a sweeter concept of judgement. It has two aspects. The first is the idea that "judgement" refers to what we use when we have run out of formulaic guides, check lists, and algorithms yet still have to carry on thinking - to use our judgement. Judgement of another's process or product is then inevitably a matter of independent thought coming to terms with other independent thought. The first question is then how these two strands of thought may in principle meet in public. Judgement, thus any kind of assessment is about the hope for a public space.To see these dilemmas in terms of anxiety about paradigms of knowledge might strike us at first sight as odd. For even in these Gradgrindish times, on the most rigidly unimaginative conception of academic assessment, well before we approach the contentious areas of art and design assessment, other categories of criteria tend to even now to be acknowledged. Guidelines and "benchmarking" documents refer to skills (even "transferable skills" of course) and to "understanding" and to "independent thought".On this account only part of any assessment criteria lists knowledge of bodies of facts, or even collections of recalled theories or opinions, the bulk of the set of criteria identifies quite different things, not listable information but recognisable and shareable virtues. This rather obvious (Rylian) point can easily and harmlessly finessed by extending the term "knowledge" from various sorts of knowledge of what is the case to various, equally widely assorted, forms of knowing how to do more or less admirable or useful things. To be sure if we are determined to suppose that what is assessable is all sorts of knowledge there is no doubt that we can construct a capacious enough hold-all to carry most of what we want into most sorts of examinations. (There can be no doubt at all that within the history of art and design we will find items of kinds of knowledge that would fill the most capacious of portmanteaus - and at different times the rejection of most of them). The task left to us (of assessing assessment) might then seem to be the fairly simple one of unpacking these hampers and sorting their contents. In fact I think the idea of this being a simple task is an illusion. Before we ask what can be known we should ask what could be shared.If we are to address concepts of knowledge within the context of education in art and design we must of necessity approach it via the idea of (admittedly puzzling) idea of communication. This is an old problem: it is not a recent dispute whether art (or art and design) communicates. Kant introduced at the heart of his discussion of judgement about the arts what we might call "maxims of communication", acknowledged by him as a digression on what he called "maxims of common understanding" (think for yourself, think from the standpoint of everyone else, and be consistent). He thus tacitly acknowledged how puzzling this idea can be. I shall attempt to reconstruct what I take to be important in this discussion for our present concerns. I shall then attempt a sketch of what minimal concepts of knowledge we need in order to secure and defend what we to, or ought to value in education in art and design.I argue that Kant was essentially right in his view that where "common understanding" is aesthetic it must communicate by the products of an essentially creative process, that exhibits what he called "spirit". It lies at the core of his account that we then communicate by demonstration, rather than by "precepts". The price we have to pay for acknowledging this is, however, that we then have to think of the products of art and design (works of art and design themselves) as objets of knowledge in their own right. This might have radical consequences for the defence of education in this area from the pressure of our educational masters.