As executive vice president and CTO of asset management firm Northern Trust, Nirup Krishnamurthy leads a global technology organization with 1,100 employees. With an organization that size, Krishnamurthy has to do a lot of hiring. He's learned to pick perfect IT workers through experience, and he's been in IT since 1995.

If Krishnamurthy's name sounds familiar, it may be because he served as CIO of UAL, more commonly known as United Airlines, before joining Northern Trust in 2005. He worked for United for 15 years and earned his stripes as an effective hiring manager inside that company. Krishnamurthy spoke with executive recruiter Jane Howze about definition of a successful hire, how he ensures that job prospects will fit with the rest of his team, why candidates have one chance to wow him in an interview and what they need to do to impress him.

CIO: What types of positions do you hire for as CTO of Northern Trust?

Krishnamurthy: Right now, at Northern Trust, I'm interviewing senior information technology executives, trying to fill positions in my organization, which has seven divisions in technology with 1,100 employees worldwide and 600 or so contractors, so a total staff of 1,700. The people I interview are all leaders in information technology.

Who was the first person you ever hired? What company were you working for and in what capacity?

The first person I hired was when I worked at United Airlines. I was a team leader for an IT project we were implementing. I needed to hire a programmer with specific skills and experience in a real-time system. That was my first hire in a management capacity.

What did you base your hiring decisions on when you worked for United?

One of the things I did when I first began hiring at United Airlines was to create my own multiple-answer questionnaire, which tested for basic programming, logical thinking and situational reaction skills. Just to get a baseline, I had employees take the test anonymously so I knew how to calibrate my requirements. When I became a manager for the group a year or two later, the process I created became very popular, and human resources started using it in their hiring process.

Did you receive any training about how to hire early on?

There was no hiring training at United. I followed an interview process that was set in place by the company.