Maxine Powell, who was responsible for developing the charm, grace and style of Motown Records’ artists during the Detroit label’s 1960s heyday, died Monday at age 98. Motown Historical Museum CEO Allen Rawls said Powell died of natural causes at a hospital in Southfield, Mich.

She didn’t sing or write songs, but those associated with Motown say Powell was as essential to the label’s operations as any performer or producer. She directed the label’s Artists Development Department, also known as “Motown’s Finishing School.”

Through it, she emphasized to many artists — including Smokey Robinson and the Miracles, the Jackson Five and the Supremes — how they should carry themselves, treat people and dress.