In order to protect the privacy of subjects, a necessary step prior to sharing of any clinical data is to de-identify the data. However, the process of de-identification may impact the results found in a re-analysis, or prevent such a reanalysis entirely. Additionally, while there have been some general proposals on the methods to use for de-identification, the actual implementation can (and does) vary across the Pharmaceutical Industry. This may lead to difficulties in combining data across Sponsors and interpreting results. This talk will review the current de-identification processes used in the Pharmaceutical Industry, highlighting their differences and the potential impact on reanalysis and/or new analyses. Suggestions will be made to help minimize the impact of de-identification on such analyses.