You wouldn't buy a car on the basis of only a written description and a few kicks to the tires. Why would you make a potentially equally costly decision about whom to hire without also asking for a test drive?

That's the premise of an in-depth recent article in The New York Times examining what the paper says is a new trend in startup hiring--trial periods for potential new employees. Featuring interviews with executives at around half a dozen fast-growing, young businesses, the article by Sarah Max is well worth a read in full if you're seriously considering jumping on this bandwagon. But to give you a flavor of what you'll find within, here are some of the questions Max sets out to answer about the practice.

What if the person already has a job?

The best talent probably isn't spending time eating chips on the couch--most folks who are great at their work already have jobs (especially techies). So how do you persuade a gainfully employed candidate to quit his or her job to come try out for your team? In short, you probably don't--at least not immediately.

A smaller paid consulting project that can be completed during the candidate's off hours (assuming this doesn't violate the person's existing contract) works for recruiting software company Entelo. "About half of the 30 people who have been asked to work on a trial basis have moved into full-time jobs," CEO Jon Bischke told the Times. "In some cases it didn't work out because the candidates had a change of heart." In others, Bischke said, "Let's just say that had we hired them, we probably would have had to fire them."

At Weebly, promising candidates are asked to take a week off from their current gig to come and complete a paid test project. "The process is intense," CEO and co-founder David Rusenko explained. "Candidates get about three weeks of work to complete in a week--and not much guidance. It's 'Here's your desk and some people you should know.'" 

But won't you scare off candidates?

Nope, claim a couple of executives interviewed. "We've found it actually helps with recruiting," Weebly's Rusenko reports, adding, "I've had people say they can't imagine accepting a job just a couple of hours after meeting someone." Mona Bijoor, CEO and founder of Joor, agrees that many would-be employees see the arrangement as a two-way audition: Potential hires can decide if they like the work and the company and the startup gets to test out the candidate.

Do trial periods work for all sorts of roles?

The short answer is no. While they're particularly good for hiring those with little work experience, as well as designers, developers, and customer support pros, for executive and sales positions, these sort of try-before-you-buy systems can be extremely problematic. For executives, that's because they generally have a longer track record by which to judge them. For sales folks, it's hard to grasp their effectiveness during a short trial. "In sales," Bischke says, "you're going to need several months to build a book of business until you know someone has really hit their stride."

How's retention?

At the companies the Times talked to, it seems pretty great. At Joor, for example, the attrition rate these days is down to 10 percent. Three years ago, it stood at 60 percent. Several other companies profiled offer similarly positive statistics showing that once people make it through the test-drive process, they tend to stick around.

Have you ever used trial periods as part of your hiring process?