The "Appendices" on the Lord of the Rings Extended Edition releases are extensive, behind-the-scenes documentaries that provide a detailed look into the making of the films. They mirror the appendices in Tolkien's book, offering supplementary information beyond the main storyline. Each film's Extended Edition has two bonus discs dedicated to the Appendices, containing numerous featurettes and documentaries.

The Hobbit Blu-ray Extended Editions feature extensive documentary material called "Appendices". These appendices are detailed behind-the-scenes documentaries that delve into the creation of the films, including casting, set design, visual effects, and more. They are often more extensive than the films themselves, providing a comprehensive look at the filmmaking process.