This article on coproduction in the consistently excellent Guardian Public is well worth a read.
The standout passage:
The challenge will be when people come to fully understand how coproduction alters the relationships between commissioners, providers and users[:] it challenges our view of who the customer is.
Rather than identifying, codifying and making the case for resources to meet ‘needs’ and then looking to get these needs purchased by a third party (the commissioner who we often regard as the customer) we should be focusing our efforts on creating demand…
Coproduction is a way of building demand from, by, and with.
arbitrary constant 