Recently, I've been reviewing the interview advice I have offered over the years in my Tooling Up column. I've come to the conclusion that I have done readers a disservice by failing to address a very important part of job interviews. So far I haven't written about your questions.

Nothing says more about you than the questions you ask at a job interview. Insightful, thought-provoking questions—fact-finding questions posed in upbeat and optimistic tones and job-related questions that show you are interested in and knowledgeable about the position—can be powerful, positive signals to a potential employer. They show that you're interested and engaged. And you shouldn't wait until the interview day to start asking questions.

Questions before the interview day

You’ve received an invitation to a job interview. Congratulations! But don’t wait until the interview day to whip out your list of questions.

I have never understood why some applicants fly blindly into their interviews when if they only asked a few questions ahead of time they would be much better prepared. Maybe they’re so full of enthusiasm that they forget to ask questions, or maybe they think it's cheating to request more information than the company volunteers. But trying to get a job isn't like trying to get a good grade on an exam. You don't have to worry about appearing to compete unfairly. As long as you're ethical about it, seeking an advantage is seen as a sign of desire and enthusiasm.

Read “Interview Intangibles” for more interview tips.

Here are some questions you’ll want to ask your main contact at the company, before the interview:

• "Can I get an agenda with the names and titles of all the people I'm likely to meet with?" (Once you have the list, you can look up their work on PubMed and their profiles on LinkedIn. You might want to request a connection, but wait until after your interview.)

• "What attire is recommended?" (There's no need to guess. You don't want to show up in business casual and find that everyone else is in suits.)

• "Who will be in the audience during my presentation? What are their backgrounds?" (You need to know this to prepare an appropriate presentation.)

• "What is the structure of the interview? Will the day consist of a series of one-on-one meetings, or will there be panel interviews as well?"

Every company does interviews differently, so don't assume you know how things will go. The fewer surprises you encounter, the better.

Now, on to the interview day …

Questions to clarify

Sometimes it’s OK to answer a question with a question, and here's a great example: “Tell me about yourself.”

It's a maddening question—and a very effective one for an interviewer—because it's so open-ended. It could mean anything. So what's the best approach? Should you just guess the questioner's intent and forge ahead? (“Even as a 4-year-old I was fascinated by biotechnology.”) Wouldn’t it be better to ask a simple question?

• I’d be happy to do that. "Which part of my background would you like to know about?"

No interviewer will object to questions that seek to clarify their intent, and few will refuse to answer. They want you to provide the information they are seeking. And once you’ve made it to the interview stage, they want you to succeed. They hope you're the ideal candidate. And anyway, nobody likes to be involved in an awkward interview; it's awkward for the interviewer, too. So, let your interviewer help you. Request the information you need to answer the question in a satisfactory manner.

Questions about the company and its mission

The best candidates come prepared with lots of information about the organization they're interviewing for. They know about the company’s Alzheimer’s program and its new partnership with Merck.

Becoming informed about most companies isn't hard. With the exception of tiny start-ups, every company in this sector is visible on the Internet, and you’ll find plenty of press releases, news articles, and financial reviews all across the Web. If it's a public company, you'll find regulatory documents on EDGAR, the U.S. Securities and Exchange Commission’s electronic data system. Some of them make good and useful reading; you'll quickly learn to recognize and skip the boilerplate. Always go to the company’s Web site and read what you find there.

Study these resources and build a list of questions. Take along a notepad listing queries about the company's mission. Aim to understand where the company is headed and how that might relate to your career ambitions.

Some examples are:

• “It looks like ABC Company is pursuing a number of new anti-infectives. With the high morbidity associated with infections caused by multidrug-resistant bacteria, I would think that the majors are all investing heavily here as well. What kind of edge does ABC have in such a crowded category?”

• “I love the idea of taking tools from synthetic biology to develop organisms that produce commercial products from sustainable sources. But I would think that even a state-of-the-art effort like that would require techniques from microbial physiology or chemical engineering to move into fermenters. How does XYZ AgriBio plan to combine high-tech with old-school in order to scale up and commercialize?”

You want to recognize that you have studied the company’s mission, but this is not about showing off. This is your future; you want to discover as much as possible so that you can make good decisions. Employers will be impressed if you show genuine interest and curiosity, particularly about how the work you might be doing there relates to the company's mission.

Expect to discover less information about start-up companies. That's fine; for an entry-level position, they won't expect you to know things that aren't public knowledge. You'll just have to learn about the company by asking more questions. And just as with more established (and visible) companies, questions about how your skills relate to the company's mission are sensible and will make a good impression.

• “I understand that the team I would be working with is pursuing new directions in the area of anti-infectives. I’m a microbial physiologist, so I’d love to know more about the company’s plan to incorporate pathway-engineering methods into drug development. Can you tell me more about the role that your microbiologists have (or will have) in the product development phase?"

When asked carefully, questions about the company’s financial standing are fair game; keep in mind that financing is almost always a great source of anxiety for people at early-stage companies. So save such questions until later in the interview, when you've established some rapport. And be delicate.

• “I would imagine that the R&D overhead on something as sophisticated as synthetic biology for bio-based sustainable chemicals is quite high. How's the funding effort going so far, and how long will your current funding last based upon your burn rate?”

Questions for your prospective boss

Nothing is as important as the relationship you develop with your future boss. To start off on the right footing, you need to ask good questions. Here are some examples:

• “Can you tell me about a particularly successful hire you’ve made? What characteristics made him or her successful?”

• “How would you describe your management style?”

• “How are work goals set for employees—me, for example—and how often would we meet to discuss my progress?”

• “What kind of turnover does your team have? Can you tell me about someone who didn't work out? What was it about that person that made them a poor fit for the company?”

• “If you could wave your magic wand and improve three things in your department, what would you improve?”

Be cautious about tone and style

When I give a seminar about this topic, I always make a point about the tone and attitude, or style, of your interview questions. But it's difficult to convey intonation in a written column, so let me put it this way: Your questions should never sound critical. Always ask them in an upbeat, enthusiastic manner. If you ask about a small company’s cash reserves, don't reflect the skepticism of the analysis you read at Yahoo! Finance. Never force the company to defend its viability. Always act as if you're eager to hear good news.

It's true that how you answer interviewers' questions is hugely important in determining how you are perceived. But questions you ask yourself add to how they perceive you, in important (and sometimes decisive) ways. This is one aspect of your job search that you're totally in control of.

A writer and speaker on career issues worldwide, David Jensen is the founder of CareerTrax Inc. and managing director of Kincannon & Reed Global Executive Search.

10.1126/science.caredit.a1200106