A lot of organisations are matrix organisations, which require  work across the borders. Normally  communication can work better within than between  organisations. A part of this is because we have different managers, but not all of it. Integrating the supplier in the development work means that they can influence the solution so that we end up in a solution that can be easily produced in their factory. But it also means that you focus only on one supplier too early and agree on the price real early 2+4 PPP