BACKGROUND: Identification of MS registries and databases that are currently in use in Europe as well as a detailed knowledge of their content and structure is important in order to facilitate comprehensive analysis and comparison of data.METHODS: National MS registries or databases were identified by literature search, from the results of the MS Barometer 2011 and by asking 33 national MS societies. A standardized questionnaire was developed and sent to the registries' leaders, followed by telephone interviews with them.RESULTS: Twenty registries were identified, with 13 completing the questionnaire and seven being interviewed by telephone. These registries differed widely for objectives, structure, collected data, and for patients and centres included. Despite this heterogeneity, common objectives of the registries were epidemiology (n=10), long-term therapy outcome (n=8), healthcare research (n=9) and support/basis for clinical trials (n=8). While physician-based outcome measures (EDSS) are used in all registries, data from patients' perspectives were only collected in six registries.CONCLUSIONS: The detailed information on a large number of national MS registries in Europe is a prerequisite to facilitating harmonized integration of existing data from MS registries and databases, as well as comprehensive analyses and comparison across European populations.