Thorsten, In a couple of places the docs for Boost.Range talk about 'nested typedefs': 1) In the first paragraph of boots_range.html: "The subset deals mostly with iterator returning functions and nested typedefs." 2) In the first paragraph of external_concepts.html: "The concept can be specified as a set of member functions with well-defined semantics and a set of nested typedefs with well-defined properties." In both cases, I think it would be more appropriate to talk about 'nested types.' The subject of the first sentence is standard library containers, whose iterators can be nested classes. The second sentence is about generic programming in general so the same considerations should apply. The article 'Generic Programming Techniques' says that associated types are 'typically' member typedefs or associated externally throught traits, which I think is slightly more accurate. Jonathan