American fashion mogul Andrew Rosen launched Theory with contemporary designer Eli Tahari in 199, with only pants in a new spandex. They were incredibly popular, growing eventually to a women’s collection focused on flattering, precisely tailored pants and sleek shirts at contemporary price points. Based in New York, Theory makes sophisticated and comfortable modern clothing. “Clean silhouettes, quality, craftsmanship and fit” are the focus. Make this your go-to brand for tailoring and separates that are cool but never obvious. Known for flattering silhouettes, Theory is one of the most popular contemporary brands worldwide.