We have a wide and varied experience of data mapping and migrating historical client records from a number of different sources. This varies in complexity from simple spreadsheets and Access data bases, to more complex Windows and web based systems. OPMS requires that data is cleansed i.e. for clarity this means that each client episode of related data will conform to NDTMS validation rules. OPMS can run a range of validation routines and reports to assist the local client data officer to validate the migrated historical records prior to 'sign off'.