This introduction works to shape the sense of affect inquiry as a multivalent field of study. Whereas the first volume's introduction was titled “An Inventory of Shimmers,” this collection advances a “Shimmer of Inventories”—in other words, it argues for an affect theory that is as contingent to its situation, flexible in its disciplinary orientation, and rigorous in attending to the particularities of intensive encounters. The introduction offers some guidance about the practices of affect study and its unique take on the relationship of theory and practice. It also overviews the themes that organize the book's sections and their chapters.