Sequenced Collections, targeted for JDK 21, are a new collection type created to represent a sequence of elements with a defined encounter order. Ana recorded this episode with Stuart Marks, the owner of JEP 431 about Sequenced Collections. Stuart discusses the essence of Sequenced Collection interfaces, what needs those address and how they fit within the existing Collections framework. He explains the design of Sequenced Collections, architectural decisions and particularities of the API. He also shares his view on how Sequenced Collections can inspire future Java platform developments.