The Life is Marketing Blog has a post titled 'What Makes a Good Advertising Client.' Some highlights ...
- Choose the right agency for you in the first place.
- Understand how agencies work.
- Agree on what you're trying to accomplish.
- Trust each other.
- Know your limitations.
- Understand advertising.
- Understand your product.
- Respect time.
- Understand the money.
- If you treat your agency like clerks, you'll get the shelves restocked--and not much else.
It's a good list [read the full post here]. For me [and I have experience on both sides] it boils down to this ... If you are going to pay a lot of $ to engage an agency, then (1) Commit the proper resources to managing the agency (2) Commit to establishing an internal process for how to interface with the agency (3) Understand [and communicate internally] the agency's role.