David Wertheimer is the director of strategy for Alexander Interactive (Ai), a New York-based ecommerce strategy, design and development agency. David has a diverse background with expertise in online communication, marketing, ecommerce and the user experience. He leads Ai's strategic initiatives, from usability studies to data analysis, and provides focus and vision to front- and back-end web development projects.

David has been bringing brands to the Web for 12 years. In his years online, he has been a designer, manager, director, blogger, author, columnist, educator and public speaker. He has created world-class media websites for The Economist and Billboard magazines and drove 200 percent growth in online retail sales as the marketing director for Clarins USA. He also has worked in consulting roles for a wide range of companies, including Yahoo!, HotJobs and Rodale.

David has an MBA from the New York University Stern School of Business and a bachelor's degree from Franklin & Marshall College.