Emerging from the discussion was the conviction that relationship lies at the heart of how this can be done. If partnership is to be real, then it will be underpinned by a relationship of trust. This means (obviously) that the contract is not what makes a partnership really work - although a bad contract can wreck it. Thus the contract's role, in reality, is to define outcomes, to lessen the likelihood of things going wrong, and to address what happens when something does go wrong.
Trust is a moral term. As I form a view about whether or not I will choose to trust someone, I am making (at least in part) a moral judgement about their character and likely behaviour -based on my perceptions. I may form a low view, and still choose to trust them, but I'm making a moral assessment, none the less. The same applies to organisations. The obvious, and non-controversial, conclusion is that business has a moral dimension. I note, though, that relationship, necessitating the forming of moral judgements, is desirable, and a key for success in sourcing.
At a bit of a tangent, admittedly, this resonates with questions about the nature of law. I suggested that sourcing contracts are there to stop things going wrong, and to address the situation if they do. That's a classic view of what laws are for - and one that relies on agreement re right and wrong (or on the ability of one group to impose their view on the whole). I find it interesting that we seem increasingly to be passing laws to enable behaviour, rather than restrain it (eg The Human Fertilisation & Embryology Act of 2008) - and we're doing so in areas where agreement is far from uniform. That troubles me.