This week, I’m not writing about investing on behalf of clients. Instead, I’m writing about investing in your firm by hiring staff. Finding, interviewing and hiring is one of the toughest tasks in running a business, as you never really know how a person is going to fit.

I got up very early one morning to meet up with Mindy and Howard Diamond, president and managing director, respectively, of Diamond Consultants in Chester, N.J. They are best known as recruiters for wirehouse reps but have expanded far beyond that to serve independents and larger RIAs. Over the past 12 months, the Diamonds have added yet another service: consulting with smaller firms to figure out what kind of talent they need, whether they’re offering a reasonable value proposition, and how to go about the interview process. Needless to say, they’re called in for a lot of succession planning.

Having done a lot of interviewing myself recently, I asked Mindy how to go about it better. Her philosophy: hiring should be less about “what can you do,” and more about “who are you?” The interview is all about that, and your task as the interviewer is to get beyond the bland, agreeable, best-behavior persona of the job-seeker.

“Hiring is a game of Guess Who,” Mindy said. “The face is covered. You have to ask questions to uncover the face. Whether or not you make an offer, you win the game if you discover who the person really is and you can decide whether that person fits the culture of your firm.”

Of course, it is important to like a person you’re going to work with, and to know that his or her work style and values fit your own, she continued. You spend a lot of time working and that, ideally, should be a pleasant experience.

“There’s no talent shortage out there,” she says, so long as you’re looking for an advisor with $30 to $100 million under management. The trouble is finding advisors with the ability and vision to be successor. “That’s true in any industry, not just the advisory space,” she observes.

Nevertheless, Mindy cautions, don’t hire in a hurry. “Hiring badly is worse than not hiring at all. Bringing a bad actor or a culture killer into your firm has reverberations beyond having to fire the person. Word spreads and recruiting a replacement gets tougher.”