Dear Sir or Madame, The project „Exposing Complex Objects for Repositories“ focuses intensely on compound objects. Its objective is to extend current practices of describing those objects with respect to their visibility, interoperability and long-term preservation. Publication objects contained in the partners (hbz-NRW and the Bielefeld University) repository environments (Fedora and OPUS) are a starting point of these investigations. Draft recommendations and guidelines were derived from a contextual analysis of these information units. We would like to discuss our first results with experts, that are familiar and experienced in one of the fields of modeling compound objects, metadata standards and repository systems. We are very pleased to invite you to attend the workshop which take place on Nov. 11th and 12th 2010 at the Library Service Center in Cologne (www.hbz-nrw.de) The first draft of the Report on Enhancing Interoperability between existing Open Access Publication Infrastructures (http://www.eco4r.org/workshop2010/downloads/eco4r_report_compoundobjects_draft.pdf) and a preliminary workshop program (http://www.eco4r.org/workshop2010/Programme-eco4r-Experts-workshop.pdf) are now available for download. You have also the possibility to subscribe to our mailing list at: http://listen.hbz-nrw.de/mailman/listinfo/eco4r Yours Sincerely, eco4r team