Bill Greening has been a Barbie collector since 1989. After earning his B.A. in fashion design and textiles from Cal State Long Beach, he joined Mattel as an Assistant Designer a decade later. In 2006, he transitioned to the Barbie Signature line, specializing in collector dolls. Greening is responsible for conceptualizing prototypes for new Barbies before they enter production. He is part of a newer generation team, which includes Robert Best and others, taking over the Barbie world from predecessors such as Carol Spencer.

In 2000, he released his first creation, Cool Clips Barbie, and since then, he has designed a variety of dolls and collections, including the Tina Turner, Cher, and Supergirl from the Flash movie.