Hypermedia composite templates define generic structures of nodes and links that can be reused in different document compositions. The XTemplate language is an XML-based solution for defining composite templates for hypermedia documents in order to embed semantics into a composition that does not have it in prior. The use of templates intend to facilitate the authoring of interactive applications in Digital TV systems, as long as IPTV systems. XTemplate 3.0 extends the previous XTemplate versions, incorporating new features to the language and increasing its expressiveness. As an application of XTemplate, this work extends NCL (Nested Context Language) with XTemplate, adding semantics to NCL contexts and providing document structure reuse. Categories and Subject Descriptors D.2.13 [Software Engineering]: Reusable Software ; D.2.11 [Software Engineering]: Software Architectures General Terms Languages Keywords Interactive TV, NCL, Composite Templates, Reuse, Composition Semantics, X...