Mike Carlton, Carlton Associates, has published a new whitepaper with a great perspective on better understanding of clients. It is titled: "The Client Trilogy" and can be found on his web site.

Another resource that Mike has pointed out to me is knowledge@wharton. The Wharton School of Business at the University of Pennsylvania in Philadelphia is one of the top business schools in the US. This sight offers some fabulous free articles, including: "Hiring from Outside the Company: How New People Can Bring Unexpected Problems."
There is some great stuff on this site, take a look.