In this book a peer-to-peer file sharing system between mobile devices is designed and implemented using Bluetooth as a communication protocol. The application allows J2ME and MIDP (Mobile Information Device Profile) enabled mobile devices to share and publish the files in the network over Bluetooth, search for specific types of files such as (music, picture, text, and program) and download them onto its local memory. It is possible to develop the system in the future, to add more features and the capacity to work on more than one operating system for mobiles.