Yesterday I heard words from a new client that made my face light up, as it's the kind of client relationship I think we all truly seek: thought partnership.
If designers want to be seen as agents of change, not mere decorators, we need clients to see us as thinking about their needs outside of the work at hand.
Standing tall as a holistic thinker, you can enter into larger, bolder discussions that will help shape and change more than just their marketing -- you'll change the quality of their business. You'll show them an outsider's perspective on their customers, the community they play in, and their overall corporate strategy and brand. Otherwise, you're just taking orders. Without being a party to the larger discussions happening within your client's organization, you can't begin to originate the kinds of ideas that can create positive change on a large scale for the good of their customers.
That said, don't forget the "partnership" part of your role. Just because you're orbiting the client's hairball (to borrow Gordon MacKenzie's phrase) doesn't mean you get to take pot-shots. A good portion of your designer-client partnership is being cognizant of how your ideas are going to influence their organization. Some ideas you originate and share with the client will change the way they do business. The same goes for you. The client often shares ideas with you that dramatically influence how you do business. It's a two-way street, and many designers forget in the heat of the battle over which concept and what idea that without the client there to support your business, you don't have a business. And without the client being part of the ongoing conversations you're having to help grow their business, then you're just designing things on demand instead of really making a difference.