In Sourcing

Similar to OutSourcing, but done on the customer's premises - which allows ExtremeProgramming to be easily used.

"What if you gradually replaced the members of the team with technical folks from the customer? I call this 'insourcing'." quote from Kent Beck's book ExtremeProgrammingExplained.

I really like this idea. It doesn't focus on holding the customer at ransom so that you can get a little bit more money out of them for maintenance.

Which explains why it isn't going to happen. Lacking an insourcing culture, how is the customer going to demand it happen? And lacking customer demands that it happen, how is it ever going to happen save developer altruism?