Slides of the talk at ECMDA 2011, Brimingham, June 2011 ABSTRACT: The package is one of the basic UML concepts. It is used both to group model elements and to provide a namescope for its members. However, combining these two tasks into a single UML concept can become not only too restrictive but also a source of subtle problems. This paper presents some improvements to the current UML naming and grouping schemata, using the ideas proposed in the reference model of Open Distributed Processing (ODP). The extensions try to maintain backwards compatibility with the existing UML concepts, while allowing more flexible grouping and naming mechanisms.