Data swapping is a statistical disclosure limitation practice that alters records in the data to be released by switching values of attributes across pairs of records in a fraction of the original data.

Web Services are an exciting new form of distributed computing that allow users to invoke remote applications nearly transparently. National Institute of Statistical Sciences (NISS) has recently started hosting NISS Web Services as a service and example to the statistical sciences community. In this paper we describe and provide usage information for NISS WebSwap the initial NISS Web Service, which swaps one or more attributes (fields) between user-specified records in a microdata file, uploading the original data file from the user's computer and downloading the file containing the swapped records.