The Unicode Roadmap Committee (Michael Everson, Rick McGowan, and Ken Whistler) maintain the list of scripts that are candidates or potential candidates for encoding and their tentative code block assignments on the Unicode Roadmap page of the Unicode Consortium Web site. For some scripts on the Roadmap, such as Jurchen, Nü Shu, and Tangut, encoding proposals have been made and they are working their way through the approval process. For others scripts, such as Mayan and Rongorongo, no proposal has yet been made, and they await agreement on character repertoire and other details from the user communities involved.