Working plan: The working plan provides for the assessment of functional outcome and quality of life by means of validated tools (TESS, SF36, PEDQOL) and objectively measuring daily activity patterns by using the Step Activity Monitor (SAM) in 600 long-term Ewing sarcoma survivors and a control group of 300 matched healthy subjects. Information on sarcoma treatment and follow-up is obtained by re-structuring and complementing the database of the relevant patient cohort (n=3000) from four consecutive nationwide and international clinical trials between 1980 and 2008. Procedures of local treatment will be evaluated regarding functional outcome, quality of life, and survival probability and prognostic factors predicting long-term outcome will be identified.