It depends what your threshold of pain is. White, an IP based in Minneapolis, Minn., has written direct-mail packages for 21 years. He's not only learned to say no, he's figured out how to make himself look good while delivering the bad news. This gives the impression that your services are in high demand and therefore valuable. By stating up front what his planning needs are, White gains respect, if not always jobs.
Clients understand that.
I still get into that situation. If you take on too much and fail to meet the deadline, you might lose the client. These are people in the same business, who work similar to the way I work, use some of the same tools, and have the same base philosophy. Some IPs might worry that they would lose potential clients forever by referring them to other professionals. What goes around typically comes around, though, especially within a tight and supportive network of colleagues.