At the fashion website Net-a-Porter, what began as a small selection of items from 11 beauty lines has, rather predictably, grown exponentially over a couple years to include 180 brands.  The person heading up that expansion is, however, something of a surprise: a brawny 41-year-old, typically dressed in an understated Alfred Dunhill suit and traditional Hackett button-down. It would be far easier to imagine him poring over investment portfolios or legal documents than moisturizing night creams, eaux de toilette and sheer-finish lipsticks.  “I do get that reaction from a lot of people,” said David Olsen, the vice president for global beauty and grooming at the Net-a-Porter Group. “They don’t expect a middle-aged man with a wife and three children to be the beauty guy.”  Not that being the beauty guy doesn’t work to his advantage in some ways. “I can look at products from a different angle,” he said. “I’m not going try an eyeliner or mascara. I’m like: ‘Is this going to sell? Is this going to make women happy?’”  Mr. Olsen has spent the last 15 years focused on what appeals to beauty buyers shopping online. In 2000, straight out of graduate school, he set up a website for his mother, Dr. Margaret Olsen, to sell the skin-care products carried at her Los Angeles dermatology practice.  “I was just kind of learning as I went,” he said, in spite of his joint J.D. and M.B.A. degree from the University of Miami. “It was business school on steroids, essentially, because you had to be responsible for everything.”  His garage was the site’s warehouse. Gradually he expanded the operation to include the websites of hundreds of other doctors and medical spas. In 2009, it was acquired by the online retailer Dermstore, where Mr. Olsen eventually became vice president for business development and operations, and more than tripled the number of brands offered.  At Net-a-Porter, he has assembled a deliberate mix of niche labels, like Sarah Chapman and James Read, with what he calls “the big boys” — widely available brands like Lancôme and La Mer. As with the website’s fashion offerings, the selection from each company is for the most part cherry-picked rather than comprehensive.  And purchases, even of comparatively low-ticket items like a Charlotte Tilbury $7 eyeliner sharpener, are typically delivered in smart, ribbon-tied black boxes. According to the company, its sales of beauty products have grown by 400 percent since it started selling them in March 2013.  Mr. Olsen often gets product recommendations from the website’s largely female staff, as well the editorial team of its print magazine, Porter. And although he doesn’t typically try out cosmetics, he confessed to being, as he put it, “an eye-cream fanatic.”  He does test the skin care products and many of the grooming items sold on Net-a-Porter’s male-centric arm, Mr Porter, which is also under his jurisdiction. When he refers to products he’s particularly fond of, like Rahua shampoo and a lavender-scented pillow spray by This Works, his enthusiasm is pronounced, akin to that of a football fan talking about his favorite team.  While well-documented changes have taken place at the Net-a-Porter Group in recent months — namely, a merger with the Milan-based website Yoox and the departure of Natalie Massenet, who founded the company in London in 2000 — Mr. Olsen remains buoyant.  “It’s an opportunity,” he said. “I’ve met with Federico Marchetti, who’s now the group C.E.O. He’s very inspiring in his own way, and he’s very focused on business. I’m really excited for what we can do with beauty and grooming underneath the new umbrella.”  First up was the introduction of beauty items on the Outnet, the website’s discount arm, which was timed to holiday shopping.  For all that, Mr. Olsen acknowledges an implicit challenge. “We’re a global company, and I’m the American,” he said, laughing. “I’m, like, the most American on earth.”
Most beauty-product buyers are women, but here it’s a brawny guy who pores over the night creams and lipglosses.