According to Bašta, the growing trend of energy provider changes will continue this year as well. Price offers of the respective suppliers still differ to such an extent that particularly larger-volume customers have a motivation for a change. However, apart from the price, companies should also be motivated by the terms of supply, such as the company's fl exibility regarding the set obligation to order a certain amount of energy. According to OTE director Jiří Šťastný, the development of natural gas supplier changes copies the number of changes in the fi eld of elektricity with a slight time delay that corresponds to the time of gas market liberation. An easier administrative procedure in connection with a natural-gas market operator also had an impact. According to Šťastný, the number of changes is also increased by the effort of customers to use a synergy effect when changing both commodities at the same time. According to Bašta, signifi cant factors affecting the number of changes also include aggressive marketing campaigns and in some cases also unfair competition practices by some suppliers related to the growing competition on the supply side. According to the ERÚ data, the number of issued licences for natural gas trading experienced a higher increase in the previous two years; while 11 licences were issued in 2009, 38 were issued in 2010 and 27 in 2011. Last year, the ERÚ issued 155 licences for electricity trading, as opposed to 90 in 2010 and 48 in 2009. According to Bašta, in the future one can thus expect a higher emphasis to retain the existing customers. A new factor is the price competitiveness of the incumbent suppliers compared with the alternative ones. Therefore, smallest suppliers' market concentration, growing competition and customer transfers both from large to small providers and vice versa as well as from one large provider to another large one are probable.