The paper examines the development of the euro market and its tendency to assume the role of the world reserve currency. It analyses whether the role of the euro in the financial markets is really increasing to the point where it could compete with the dollar. Building on the concept of international money developed by Swodbod (1969.), Cohen (1981.) and Krugman (1984.) in their analysis of reserve currencies and their driving forces, the analysts have examined the rise and fall of international currencies. The liquidity and size of the euro financial market is increasingly approaching the level of the US dollar market, although recent developments have strengthened the role of the dollar. However, the introduction of the euro has not yet led to significant changes in the composition of the world's reserve currencies, where the euro is the second most important. The US dollar remains the world's leading reserve currency because of its role in the financial markets, its credibility, its liquidity as well as its inertia in the use of international currencies. The reason that the euro has still not taken over the role of world reserve currency is also the declining share of the euro in total world reserves after the global financial crisis in developed and developing countries. The increasing importance of non-traditional currencies, whose economies are becoming more and more important for shaping the world economy, is the reason for the tendency of the euro, but also the US dollar, to have a declining share of total world reserves.