FORTUNE — Hosain Rahman and Yves Behar do what some say isn’t done anymore — they create high tech hardware, not software, in Silicon Valley. Vinod Khosla, famed venture capitalist and co-founder of Sun Microsystems, says as much: “Everyone was telling them they shouldn’t do hardware, that it’s a huge risk — and it is. It takes crafting a whole new method of what works, which they did.” Rahman and famed designer Behar are the “they” Khosla is referring to. Rahman is the CEO of Jawbone, Behar is the company’s chief creative officer, and together they have made revolutionary Bluetooth headsets, the most popular wireless speakers in the category, and a new health wristband that can track steps and sleep patterns (among other things). How do they create? Constant vision, revision, and sweat.
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“Hosain and I are two people who have been at Jawbone longer than practically anyone,” Behar says. “Over 10 years we’ve developed an understanding, a shared philosophy that allows us to improve on our original goal — adapting products for wearability.” Rahman adds that for collaboration to work you must “put your life force into each project,” which is to say: Be dedicated.
“When we started with headsets,” Behar continues, “it was the hardest thing I’ve ever worked on. I’ve designed shoes, and you hear from the customer immediately if something doesn’t fit. It’s like that, but with sound. We spent years refining, failing, and succeeding, and now, finally, we’re building on that knowledge. It’s an ongoing process.”
This story is from the February 4, 2013 issue of Fortune.