This book is dedicated to measuring and managing performance of one of the most promising sector of the economy - the telecommunications sector. Hyper competition, almost unlimited possibilities of development, rapid growth and permanent requirements for new investments, have made decision- making in telecommunications especially dependent on the quality financial information. From this starting point we have presented possibilities of the analytical tools used in the financial analysis for evaluation and performances' projecting that is of particular relevance to existing and potential investors. On this ground we have considered key determinates and presented a list of the relevant indicators that could be used as early warning signals for the risk assessment of short and long term financial risks. This book is dedicated primarily to the managers and investors. At the same time, it may be valuable for regulators in the telecommunications sector, as well as for the economic policy creators, especially in countries where the privatization process has not been completed jet.