The desk immediately to Hatfield’s left belongs to Tiffany Beers, a senior innovator at the company and the engineer largely responsible for figuring out how to make adaptive fit a reality. She is 36 years old and a former collegiate volleyball player who looks positively Portlandia in black jeans and dark brown hair streaked with gray and blue dye. Hired by Nike in 2004 to develop new air bags for the company’s ubiquitous sole-cushioning technology, she quickly became known for her tenacity and talent, and after less than a year on the job, she was approached by Hatfield with a special assignment. For 17 years, he explained, ever since their Back to the Future brainstorming sessions in 1988, he and Parker had been giving deep thought to how athletic shoes ought to advance, and they’d come up with a set of ideas they dubbed “adaptable performance.” It was, Parker says, the “next phase of performance”—athletic footwear that could sense the presence of a foot and trigger a motor to tighten or loosen the shoe.