The first hire was the hardest. When my co-founder, Matt, and I decided that "yes, we really are starting a company," we knew we'd need help, both with big stuff like user research and with little stuff like Ikea runs. We found a great candidate in Jess Goldband, who had the right experience, loved our idea, and wasn't daunted by how raw Iodine was. We just needed to persuade her to quit her job and make the leap.

Trouble was, she knew exactly what to ask: What's your run rate? What will you do if you can't raise more money? And what, exactly, are you guys building, anyway? These were tough questions, ones we were still thinking through ourselves. Now we needed answers so convincing that our half-baked idea would seem not only tempting but also outright irresistible. It was our introduction to the central riddle of startup recruiting.

Many entrepreneurs describe recruiting as the most difficult, most important thing they do. Their stories typically involve unicorn chases, the quest for candidates worthy of their company. But few admit to the other side of that equation: how hard it is to persuade the best prospects to stake their careers on your idea. In other words, it's one thing to find those unicorns. But it's quite another to talk them into following you into the thicket.

Of course, some entrepreneurs are born to sell. They'll tell a candidate anything to get him or her to join the company, even it's not entirely, shall we say, accurate. Not me. I've found our best tactic is cards-on-the-table candor.

First, we make our case for success. We explain how we enter the game with certain advantages: our team, our resources, our strategy, and the product itself. But the best candidates view these advantages as table stakes, and they want to know what else we're holding. So we turn it around. Rather than insist we've figured it all out, we walk through the problem we're trying to solve, and how it will demand creativity, collaboration, and a bit of luck.

In other words, we make our problem seem as formidable as possible. In our case, this requires little bluster. After all, we endeavor to use Big Data to make health care decisions easier for consumers--a difficult technology in a difficult sector for a difficult audience. But if we pull it off, we will create real value in a $3 trillion industry, as well as improve people's lives. We tell prospects we are building something that should exist but doesn't yet (for a good reason--it's hard).

Even on our best days, this isn't a sure-fire strategy. For one thing, Iodine is based in San Francisco, so we compete for staff against the titans of Silicon Valley. Facebook, Twitter, Dropbox, and other tech giants all offer big, fat salaries and pot-of-gold perks, and each has snatched away some of our strongest candidates mid-woo. But we've also had the opposite experience, where Google's riches couldn't match the simple promise of a great team working on a hard problem. Thankfully, engineers like hard problems.

Of course, this approach works with only the risk-tolerant. Folks have to be comfortable putting their future in your hands. (People with families and mortgages worry about those things--as they should--and you need reasonable answers.) It also doesn't hurt to remind rising stars that signing on is a chance to learn the startup game when it's your reputation on the line--not theirs.

That's what we told Jess, by the way. Luckily for us, she decided our crazy dream seemed plausible to her, too, and she signed on as our program manager, Iodine Employee No. 1.