In the replacement of both a radiology information system (RIS) and a picture archiving and communication system (PACS) archive, data were migrated from the prior system to the new system. We report on the process, the time and resources required, and the fidelity of data transfer. We find that for two PACS archives, both organized according to the Digital Imaging and Communications in Medicine (DICOM) information model, data may be transferred with full fidelity, but the time required for transfer is significant. Transfer from off-line backup media was found to be faster than transfer from our robotic tape library. In contrast, the RIS replacement required extensive labor to translate prior data between dissimilar information models, and some data were inevitably lost in the translation. Standards for RIS information models are needed to promote the migration of data without loss of content.