During the 20th century, most countries had their electricity production, transport and distribution organised as vertically integrated monopoly. Since the 90s more and more countries, especially in Europe, have replaced their state monopoly by an open market to manage their electrical power system. In order to settle a deregulated market of electricity, countries must adopt new methods and rules for trading electricity, planning production and managing the balance between electricity production and consumption of national power systems. In this context new tools are needed, such as software tools and information systems. This master thesis is part of an R&D project, aiming at developing software tools for the implementation of electricity markets, especially the mechanisms of bidding to buy and sell electricity on the Balancing Market. The new software developed by this R&D project is a generic software, based on a flexible model, and it should be adapted to different systems of electricity markets. The present master thesis report explains the principles and processes of electricity markets, focusing on the auction mechanisms for the purchase of electricity in real time: the Balancing Market. The report exposes different methods to regulate the stability of electricity network in different European countries (Regulation Services to maintain the balance between electricity production and consumption), and analyses different systems of Balancing Market in various countries; more specifically, it inludes syntheses of the balancing market systems in Romania, Hungary, Germany, France and the Nordic countries. From the confrontation of those systems, the basis for a new flexible model has been developed. This report aims to be useful for people who have to work on a project related to electricity market (especially this R&D project) and need to acquire the required knowledge about markets of electricity, regulation services and balancing markets (especially the market systems of Romania, Hungary, Germany, France and the Nordic countries).