The W3C POWDER Working Group has published a new working draft of Protocol for Web Description Resources (POWDER): Grouping of Resources. "The Protocol for Web Description Resources (POWDER) facilitates the publication of descriptions of multiple resources such as all those available from a Web site. This document describes how sets of IRIs can be defined such that descriptions or other data can be applied to the resources obtained by dereferencing IRIs that are elements of the set. IRI sets are defined as XML elements with relatively loose operational semantics. This is underpinned by the formal semantics of POWDER which include a semantic extension, both defined separately. A GRDDL transform is associated with the POWDER namespace that maps the operational to the formal semantics."