David Olsen, who was most recently chief executive of luxury beauty retailer Cos Bar, is joining private equity firm Highlander Partners LP as a managing director, WWD has learned. David Olsen There, Olsen will be in charge of sourcing investments in beauty and personal-care companies. He’ll also be involved with any beauty investments the firm makes. Before joining Highlander, Olsen spent three years as the ceo of Cos Bar, where he brought digital and e-commerce capabilities to a brick-and-mortar retail business. Before that, he launched Net-a-porter’s beauty business, where he brought in niche and luxury brands onto the platform. Prior to that, he founded and led DermTeam, a cosmeceutical business that was sold to Dermstore, which was eventually sold to Target. Jeff Hull, president and ceo of Highlander said in a statement that Olsen’s beauty expertise “has allowed him to closely evaluate thousands of brands and build relationships with hundreds of founders, owners and executives.”