The good news is hiring is going up. The bad news is the competition is really fierce. Here's how to get a leg up.

Move over "So, tell me about yourself" or "What is your biggest weakness?" Make way for "Why are manhole covers round?" or "How would you test a salt shaker?"

Companies from Wall Street to Silicon Valley are discarding traditional softball interview questions in favour of brain crunching teasers, riddles and logic puzzles. With so many qualified candidates competing for each position, interviewers are desperate to identify those who demonstrate enthusiasm for taking on new challenges, an appetite for solving difficult problems and a certain amount of creative audacity. They are using tough and tricky questions to see if applicants rise and shine to the challenge of surviving in today's hypercompetitive work environment or slink off into the sunset.

Microsoft and other high-tech firms popularized the practice, but now prospective employees never know when a taxing brainteaser may pop up. "What an applicant knows gets him or her through the first interview," says Ed Milano, an interviewer who routinely peppers candidate interviews with brainteasers. By the time the applicant gets to Milano, vice president of marketing and program development at Design Continuum, a product design consulting firm with offices in Boston, Milan and Seoul, the candidate's aptitude or experience are no longer in question.

For Milano to extend a job offer, he has to see how the applicant thinks under stressful conditions, the environment that often describes life at a consultancy that assists clients with make-or-break strategic design programs. "We never solve the same problem twice; every engagement is unique," Milano says. "So we're looking for people who think about new things in a new way, eager to move past established limits and are confident enough to push their team-mates over their respective boundaries."

That's a tall order for any job interview, but Milano, like many recruiters, has often found that starting with a brainteaser is effective. Logic puzzles and riddles have a long tradition in fast-moving high-tech companies where being quick on your feet is an asset. As the rest of the world has embraced the attributes of the start-up mentality of the high-tech computer company, many recruiters are adopting the in-your-face style of interviewing associated with technology-heavy industries. Some recruiters believe that brainteasers are valid tools to gauge the creativity, intelligence, passion, resourcefulness, and so on, of applicants. Others are willing to accept that puzzles are little more than interview stunts that may or may not reveal aspects of the applicant's character, but there are worse ways to assess a candidate's intellectual capacities than essentially asking him or her to think out loud.

What kinds of puzzles and brainteasers are in recruiters' tool chests these days? The questions, and the desired responses, fall into four general categories.