The collection was originally housed in several filing cabinets in and near Miwa Kai's office space in Kent Hall, which she shared with Wm. Theodore de Bary. Kai kept well-organized files, and most of her original file names have been retained. In addition to the papers she collected and created through the course of her work and personal life, she also inherited papers created by Howard P. Linton and Ryusaku Tsunoda, which she incorporated into her own files and enhanced with supplementary material and her own hand-written notes.