Sang Tanzer has joined, a family-run multi-channel provider of prescription eyewear in Germany, as chief of marketing. Tanzer worked previously as head of media sales and head of performance marketing at, a distributor of contact lenses from Leipzig. Previously, he worked as marketing expert and media planner at Unister, a marketer of web portals that filed for insolvency in July, and as head of marketing at Lunoa, an online store for Danish design. Tanzer appointed Manuel Bartsch as director of performance on Nov. 1 and Mirko Schmidt as brand manager on Nov. 15. Bartsch and Schmidt report directly to Tanzer.