Our office and the advancement office have a similar relationship.
When the advancement office went through a significant expansion recently
(about 18 months ago) we spent many hours negotiating an MOU.
It turned out to be one of those instances in which the process was
more important than the product:  we hardly ever actually cite or read the
MOU, but we understand each other's terminology and examples better now.
In general:
--if the foundation/corp wants a report back, or wants a detailed line-itme
budget, it goes through my office.
--if the foundation/corp announces an open RFP (forms, deadline, etc.),
it also goes through my office.
--I attend their "prospect clearance" meetings twice a month.
--We have (and occasionally use) a form for notifying each other of
a faculty member's interests, to save on duplicate conversations and to
assist memories.

There are many exceptions, but they generally take only a few calls to
straighten out.

Stuart Ross
CSU Fullerton