In a new study published by Reardon Smith Whittaker titled "A Client's Perspective On Agencies", there are many good insights and suggestions on how to tap into a new business prospect. In that study, 81% of respondents cited "understanding of your market" as a critical factor in their agency selection. The quality of the creative product is still important (69% said so), but I strongly believe that if you don't understand the client's business, then the greatest creative in the world won't win the account. Here is a link to that study: http://www.rswus.com/documents/Final2008AgencyClientSurvey_000.pdf
Several years ago, I spoke with Stan Richards, founder of The Richards Group, on what he considered the key ingredient in a new business pitch. Without hesitation, he replied that the ability to give the prospective client a new insight on their company or category was the key factor in winning new business. His business development team worked hard to find that insight, and then spent the majority of their presentation supporting that insight and its potential to grow the client's business.
In today's challenging marketplace, I would add the ability to help a client expand their marketing efforts into new digital frontiers is also a key factor in choosing one agency over another.
Clients are not saying to their agencies, "how can you help us make ads or a new web site," they're saying, "how much do you understand about our business in order to help us build a bridge between our brand and our customers."