Valkenburg Architecture
The Valkengburg Group was established by OUNL in March 2002, with the view to bringing together institutions and organisations from across the world involved in the development and implementation of OUNL Educational Modelling Language, and this has now been extended to IMS Learning Design. The aim was to coordinate development and publication of open source reference architectures for e-learning tools and systems based on the EML and IMS-LD reference architectures. The core membership (level 1) is an invitation only group actively engaged in producing EML-related authoring tools and content management tools, and there are at present 41 members of the group, from 21 institutions, including UNFOLD partners UPF, OUNL and Bolton Institute.

The most recent version of the Valkenburg reference architecture is shown below: