The Narrative and Design division of the Westworld Mesa Hub is headed by Lee Sizemore and is responsible for the creation of Narratives. Everything, from the hosts' appearance, to their storyline(s), is created within this division. The writer's concepts of what each Host should look like are brought to the Design department, while the Narrative department oversees the planning, scripting and logistics of individual Narratives. 
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.
The Design department is seen in the Season One episodes "Chestnut", when Sizemore unsuccessfully pithces his new Odyssey on Red River narrative to park director Robert Ford, and "The Adversary", when employee Felix Lutz from Livestock Management, shows the host, Maeve Millay, around the Westworld Mesa Hub.
|“||The Narrative Division comprises two departments: Narrative Technicians and Design Technicians. These technicians are in charge of creation of in-park storylines and characters.||”|
–Westworld Corporate Guidebook, p. 6, "Narrative" , delosdestinations.com
|“||Narrative technicians work with the department head to script host responses and to structure park storylines both major and minor. The main goal is to entertain and captivate, all while controlling for the unpredictability of guest choices.||”|
–Westworld Corporate Guidebook, p. 6, "Narrative Technicians" , delosdestinations.com
|“||The design team works in concert with Narrative to conceptualize host physical appearance - from body structure to facial detailing, and from hair color to signature sartorial features. The team coordinates with the Manufacturing Division to ensure that||”|
–Westworld Corporate Guidebook, p. 6, "Design Technicians" , delosdestinations.com