Global mobile telephone systems are experiencing rapid development with the ongoing race in satellite services. Mobile satellite systems (MSS) operators (classified as LEOs, MEOs, and GEOs), are participants in what could be the most technically complex and costly proposal in the history of the telecommunications industry. Most of the MSS, however, are faced with budgetary and financial constraints and only a few have set up considerable infrastructure such as satellite constellations. They are also faced with obstacles such as spectrum availability in rural fixed markets, and most of them are going to be involved in regulatory wrangles in regions or countries which they would serve.