We demonstrate how XML and related technologies can be used for code mobility at any granularity, thus overcoming the restrictions of existing approaches. By not fixing a particular granularity for mobile code, we enable complete programs as well as individual lines of code to be sent across the network. We define the concept of incremental code mobility as the ability to migrate and add, remove, or replace code fragments (i.e., increments) in a remote program. The combination of fine-grained and incremental migration achieves a previously unavailable degree of flexibility. We examine the application of incremental and fine-grained code migration to a variety of domains, including user interface management, application management on mobile thin clients, for example PDAs, and management of distributed documents. Keywords Incremental Code Migration, XML Technologies