The following is a tool we use as part of our corporate recruiting department audit. (Email me if you'd like to find out more about this and a free audit.)

I learned to become a better interviewer than my clients for only one reason: to prevent good candidates from being excluded for bad reasons. Too many of my clients were assessing candidates improperly, either overvaluing first impressions or using some narrow range of skills to determine competency.

Diagnose before prescribing. Every first-year med student learns this simple admonition. It should be applied to business decisions more often. In an attempt at quick improvement, we often try to implement solutions without enough information. This situation is not exclusive to HR/recruiting.

Jim is the best recruiter at LNM, a division of a Fortune 500 company. Karen is a strong marketing manager who is not looking for a job. Jim found Karen's name on ZoomInfo, and he is now cold calling her to explore the possibility of considering her for the position.

If everybody knows that one thing is true, why do so many people try something else? Most companies will tell you that their employee referral program is the best way to find top talent. Most recruiters, including me, will tell you that networking with former and current candidates is the best way to find top talent.

The best candidates always require more information as they move through the hiring process. It has been my observation that when a candidate decides they're no longer interested in a job it's because they don't have enough of the right information. The recruiter is responsible for getting it to them.

The best active and passive candidates always have multiple opportunities. As a result they need more convincing that the job you're offering is better than the other opportunities they're considering. Recruiting is not about finding and hiring candidates who need another job. Anybody can do this. Recruiting is about influencing top candidates who don't need your job to consider it anyway, and then keeping them involved at every subsequent step in the hiring process.

The best active and passive candidates always have multiple opportunities. As a result they need more convincing that the job you're offering is better than the other opportunities they're considering. For passive candidates, they need to be convinced that your job is even worth evaluating. Convincing these top candidates to proceed in the hiring process and then to accept a fair offer is what recruiters need to do to be successful. Recruiting is not about finding and hiring candidates who need another job. Anybody can do this. These candidates will do whatever you suggest.

If you want to make Performance-based Hiring a reality, having a steady source of top candidates is essential. Networking is the key to pulling this off. To me, networking represents the difference between good and great recruiting. I don't look at job boards as a primary source of top candidates. Every now and then you'll find one, but not frequently enough to count on this source. However, networking, when properly done, can be the prime source of all your best people. How to do it well is the key. This will be the topic of this edition of the Science of Recruiting. And as you'll soon discover, it most certainly is a science.

Welcome to our new series of articles, The Science of Recruiting. Over the next ten editions, we'll look at every skill and technique necessary to be a great recruiter. At the end of it all, you'll have a sense of what you need to do to take your performance and success as a recruiter up another notch or two, or maybe more.