Spend the first ten minutes talking about the position: tasks & projects, who they'll be working with (if there's group work), what skills are required/desired, etc. Then let them ask a few questions.
Then you can launch into the regular questioning. Some of my favorite questions: What were some of your favorite courses (or work-related projects, if they've been out of college awhile) in school and why? Discuss something about your life or academic/work experience you are especially proud of. Describe your experience(s) working in a group setting. Similarly, describe any experience with minimally supervised/solo projects. What skills do you think you have to offer? These are the types of questions that will (hopefully) get them talking, so you have an idea not just of their experience/qualifications, but their personality & communication ability. I had a recent experience with an otherwise qualified guy who shot himself in the foot on the groups/individual question by essentially implying that he and he alone knows the right way to accomplish a project. Another guy with a 4.0 GPA embarrassed himself with a very immature way of speaking; he clearly had no idea (nor did he seem to even care) how to conduct himself professionally.
In this tight job market, you have room to be picky; people who look good on paper may be not at all what you're looking for. Similarly, someone with a lackluster resume/transcript may surprise you.
My boyfriend just got a new job in July. At his third interview, the VP asked him, "Would you like to work here at CompanyName?" He said, "Yes, I think this is a really good fit." The VP smiled and said, "You would be SHOCKED at how many people just say, 'I guess so.'" She said she was thinking of asking prospectives that question first, and immediately dismissing them if they say anything less than YES, PLEASE!
Going off of what freakgirl said, I think you should consider asking WHY do you want to work for this company. This allows the candidate to display the research they've done (if they have), and to connect their past experiences and future goals to the current job.
A book I once read on interviews said that interviews should be structured as follows:
1) Greeting
2)Establishing common ground/icebreakers
3)Indicating purpose of interview
4)Drawing out info through question and answer (general, specific, brief and long, conversations to clarify)
5)Summarize info and understanding
6)Indicate next steps to be taken
7)Closing
One important question (that I as an interviewee try to ask interviewers as well): "Why should we hire you?"
You would be surprised how often people can't answer the "Why should I work here?" question.....prepare for that one as well.
Good advice so far. I'd add:
1. Spend some real time preparing yourself, so that you know exactly what it is you are looking for in your ideal candidate. Then design questions that will let you know if they meet those criteria (good questions have been cited above).
2. Avoid the consultant / i-banking trap of hard-core, pressure interviews involving such ridiculousness as "How many gas stations are there in the United States?". While fun (if sadistic), they don't really screen for the right people (unless you like to sit around conference rooms solving brain teasers).
3. Assuming this person will be reporting to you, be certain to spend at least as much time ensuring the person is compatible with you and the organization as you do ensuring this person is the most technically skilled. You will be much happier with someone less "skilled" who you are capable of working with than a hyper-proficient social misfit. (That said, if you can find a hyper-proficient, interesting, and generally good person, hire them!)
4. Take good notes during the interview, especially if interviewing several people. I've seen to many rounds of interviews go by where people fall into basic memory traps (first person / last person interviewed, etc.) and also where there is little substantive discussion becuase no one wrote anything down.
My boyfriend just got a new job in July. At his third interview, the VP asked him, "Would you like to work here at CompanyName?" He said, "Yes, I think this is a really good fit." The VP smiled and said, "You would be SHOCKED at how many people just say, 'I guess so.'" She said she was thinking of asking prospectives that question first, and immediately dismissing them if they say anything less than YES, PLEASE!
I've got to say that I have a real problem with this style of interviewing. It strikes me as very immature, the same sort of mindset that gets a kick out of riddles. Let's face it, what is basically being said above is that the important thing in hiring this person is how they react in a particular, contrived situation that probably has nothing whatsoever to do with their job. For example an engineering job does not require any sort of bonhommie, and an introvert, or someone raised in countries that are less prone to tooting their own horn than America is probably not going to reply in such an (IMHO) obviously fake fashion.
I guess my advice when interviewing is to remember, what the heck are we hiring this person for --- presumably it's not just to fill up an empty seat --- and to ask the person about issues related to performing that role well, while ignoring issues that don't relate to performing that role. You may have your own opinions about, eg, a would-be programmer's fashion sense, but do you really want to lose what could be the best candidate based on something petty and irrelevant?
Take in-depth references. Do them yourself. Ask hard questions. Ask whether the candidate is "very good" or a truly a "superstar". Make sure the referrers are in a position to provide useful feedback. This is the single most important part of the process. Do not let "HR" do it.
Don't do all the talking. Give them enough leash to hang themselves. Quick answers don't reveal problems.
Ask for details. Exactly what did you do that made that project a success? How did you decide to do it? Who helped you? What other options did you consider? This is a must if you want to screen out the bullshitters who pad their resumes shamelessly.
Don't forgive them if they didn't take the time to learn about the company.
Magik
Why do you want this position?
What can you give personally to such a position as this?
Do NOT ask the interviewee to reinvent the wheel. In the interview for my current employer last March, I was asked "Write code to find an element in a Java vector?". I asked the interviewer for the Java documentation and found a built-in way to do so. Exercises like this serve only to prove that I can find something in the available documentation -- it's no indication of how well I develop software.
I don't know, now that you mention it, I think it would be pretty funny to say "Ok, now that you know a little about the company, please re-invent the wheel." What do you think people would say?
I have a friend who, as he was graduating from B-school, was once asked the following question in an interview: "Name three reasons why manhole covers are round." I found this astonishing in its randomness, until I realized that it's got that out-of-left-field, think-on-your-feet thing that could be useful in certain fields that require creative technical problem solving.
(The answers I was able to come up with: so they can be moved by rolling and so they can't possibly fall in. I never came up with a third, and have no idea how my friend answered.)
Well, the third is obvious: it's hard for workers to make crude sexual jokes about a square hole. I hadn't thought of moved by rolling, though.
I think this think on your feet stuff is what Lassen was warning me away from. But I'm going to have a hard time resisting "please reinvent the wheel."
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