The article explores if financial markets, specifically the foreign exchange market, are efficient. It introduces three types of efficiency: fundamental, macroeconomic, and speculative. The study finds that the foreign exchange market shows different types of efficiency depending on the time horizon. In the short term, the market is inefficient. In the medium term, it shows speculative efficiency. In the long term, it exhibits macroeconomic efficiency, although with some limitations. The traditional view of market efficiency, based on fundamentals, is rejected across all time horizons.