The 11th revision of the International Classification of Diseases and Related Health Problems (ICD) will be developed as a collaborative effort supported by Webbased software. A key to this effort is the content model designed to support detailed description of the clinical characteristics of each category, clear relationships to other terminologies and classifications, especially SNOMED-CT, multi-lingual development, and sufficient content so that the adaptations for alternative uses cases for the ICD – particularly the standard backwards compatible hierarchical form – can be generated automatically. The content model forms the basis of an information infrastructure and of a webbased authoring tool for clinical and classification experts to create and curate the content of the new revision.