Aims: The þeld of External Fixation devices and methods is lacking uniform, comprehensive terminology and description. The aim of our work is to introduce ÒMethod of Uniþed Designation of External FixationÒ(MUDEF), which will allow simple and systematic communication, documentation and approach to this widely-used treatment modality. Methods: Developed and applied in the research lab and clinical practice MUDEF is based on 8 standard and 6 additional (elaborating) symbols (http:// www.aotrf.org, the ÒFor the orthopedic surgeonsÒ chapter). Results: Use of MUDEF providing comprehensive objective information on the External Fixation system: accurate location of the elements of external þxation device on the extremity; type and orientation of the pins or wires as well as order and direction of their placement; visual imagination of the geometry and dimension of the external þxation device. This method allows to accurately documenting any external þxation device, facilitate study of different aspects of external þxation technique and interpretation of the results based on universal and clear information of comparable data. This method will facilitate analysis of complications of external þxation technique, provide basis for clear communication in the þeld of research and publications and assisting improving existing technique and technology. Conclusions: We are suggesting and hopeful that MUDEF will have appropriate role and place in documentation in the þeld of orthopaedic practice, research and literature supplementing other existing classiþcation systems.