As Intel CEO Andy Grove once said, "only the paranoid survive." And in this economy, agencies surely seem to be taking up that motto, going all out to ensure that client service is flawless. However, it's safe to say there are very few agencies that can claim to not have lost one client over the last year. Even in good economic cycles, client churn rates are often high, let alone in this environment.

So, what are the top four signs a client is about to give you the boot?

We asked a few agency vets for their opinion. Some didn't want to answer (What, me lose a client?) But a few did. Specifically, Kevin Dugan, founder of the Bad Pitch Blog and Director of Marketing at Empower MediaMarketing gave us his take which we think is worth sharing:

1) Suddenly Nice. If you have a client who suddenly changes attitude and becomes very nice or positive, they didn't win the lottery or get lucky. They feel guilty they're about to axe you.

2) Change of Duties. If you used to sit in on specific meetings and are no longer asked to do so? This is not good. Either you're no longer contributing to these meetings or someone else is sitting in them now.

3) Ending Rituals. Those free beers the client loves to get after the monthly status meeting are suddenly conflicting with his schedule. The guy has no schedule. He has a new firm in the wings.

4) New Client Contact. Your client contact leaves the company and someone inherits the relationship or is hired into the role. Danger Will Robinson! Your best bet is to have multiple relationships between the client and the agency so no one person takes the relationship with them when they leave.