FORTUNE — Dear Annie: I’m unhappy in my current position for a number of reasons, none of which seems likely to change anytime soon, so I’ve been looking around for a new job for the past couple of months. All the career advice I’ve heard (and read) mentions that a good “fit” is essential. But nobody ever tells you how to determine whether the “fit” is there or not. I’ve had a couple of interviews lately where it seemed to me that both the interviewer and I were putting our best feet forward and saying what the other side wanted to hear, which is natural enough, but I haven’t felt I’ve gotten a clear idea of what it would really be like to work for these companies. They all say they value their people, reward individual initiative, offer opportunities for advancement, blah, blah, blah, but how can I tell if it’s all just part of the script or if they really walk the talk? Any suggestions? — Seattle Skeptic
Dear Skeptic: You’re right, this is tricky. The culture of any organization — that ineffable mix of traditions, habits, assumptions, and unwritten rules that add up to “how we do things around here” — is so complex, and so subtle, that it’s hard (if not impossible) to sum up in a few simple phrases. So, even with the best of intentions, many job interviewers tend to fall back on the clichés you’ve been hearing.
At the same time, though, you owe it to both yourself and the company to peer past the happy talk. Especially since you’re already working, “you don’t want to end up in just any new job,” says Jim Hinthorn. “You want one where you’re going to thrive — and that means finding the best ‘fit’ possible.”
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As a veteran human resources executive who is now a coach for the national career-counseling network Five O’Clock Club, Hinthorne has spent decades pondering the “fit” question from both sides of the interviewer’s desk. In his view, getting it right requires you to do a fair amount of sleuthing to learn as much as you can about a prospective employer before you meet with anyone there.
Beyond the standard homework every job seeker should be doing — like studying the company’s website and annual report, and reading up on it in the trade press — take advantage of resources like Vault.com and Glassdoor.com. “You can get invaluable insights from the comments employees and ex-employees post on these sites,” Hinthorn notes. “You might also seek out current employees on LinkedIn and ask them what it’s like to work there.”
The more specific your questions, the more useful the answers are likely to be. “You’re far more likely to find the right fit if you know exactly what you’re looking for,” Hinthorn says. So think hard about what you want in your next job, pinpointing what’s really important to you, what’s optional or negotiable, and what doesn’t matter at all. The Five O’Clock Club has developed assessment tools to help with this, spelled out in a book called Targeting a Great Career by Kate Wendleton, the organization’s founder and president. But with a little introspection, you can do the same thing on your own.
“Some of the values people want in a job are, for instance, independence, creativity, power, money, adventure, working for a cause, or having time for a personal life,” Hinthorn says. Once you’ve come up with a short list of what matters most to you, you can focus on those areas when you pose questions to people who are already there.
“To some extent everyone adapts to the prevailing culture in a company — casual versus more formal dress codes, for example — but certain things are non-negotiable,” Hinthorn points out. “And you are the only one who knows what those things are.”
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Let’s say you decide that one of your non-negotiable items is time for a life outside of work. Before going to an interview, come up with questions that will give you a glimpse of whether that will jibe with the company’s culture. “Ask, for instance, what the interviewer’s typical day is like, especially if he or she is your prospective boss,” Hinthorn suggests.
As a candidate for a senior HR management job, he once asked that question and heard that the interviewer “put in half days on Saturdays and Sundays, on top of working 12-hour days during the week and attending client dinners several evenings a month,” he recalls. “I didn’t ask, ‘Is work-life balance important to managers at this company?’ But I sure found out.”
Hinthorn also recommends asking to speak with people who currently report to your prospective boss. “Ask them what he or she is like to work for, including questions like, ‘If you could change one thing about this person, what would it be?’” he says. “People tell me, ‘I couldn’t ask that!’ But in all the years I interviewed people, I never thought anyone asked too many questions. Most job hunters ask too few.”
Talkback: What questions have you asked in job interviews that helped you identify a good (or bad) cultural fit? Leave a comment below.