The Narrative and Design division of Westworld Mesa Hub is headed by Lee Sizemore. Everything from how the host will appear to their story line is created within this division. The writer's concepts of what each Host should look like brought to the Design department.
Besides Sizemore and his narrative team, the only other person who can write narratives is Dr. Ford. After Sizemore finished writing his new narrative, he had a presentation to announce it to other Westworld employees.