Peer-to-peer (P2P) is a computational model with appealing characteristics that may bring about intriguing mechanisms for sharing cartographic data and software. It makes it easy for individual computer users to participate in the Internet not only as an information consumer but also as a provider, with or without true identities, through either fast T1 or slower phone line connections, using PCs or Macs or UNIX workstations. The prospects of applying P2P to sharing cartographic data and software are encouraging. This chapter describes how a node-hub P2P system enables individual users to form a cartographic data network where cartographic data are packaged, published, registered, searched, and transported over the Internet. The hub maintains a dynamic catalog so that metadata are up-to-date and search results are more reliable and useful. The hub also controls user participation and enforces various levels of authentication to prevent abusive usages and violation of copyrights and licenses. The P2P system also enables cartographic software components to be published and shared among participants. It accomplishes this by implementing a Universal Description, Discovery, and Integration (UDDI) register on the hub, where metadata for the software components are stored, and by incorporating the search API on the node, where search functions are tailored to cartographic software components are provided. Fault tolerance and better security measures are the major areas for improvement.