The Exchange Rate Mechanism (ERM) is a framework used to manage currency exchange rates between different countries within the European Union (EU). It was a key component of the European Monetary System (EMS), which was established in 1979 to foster stability and coordination among the currencies of EU member states.

The primary objectives of the ERM were:

1. **Exchange Rate Stability:** The ERM aimed to maintain stable exchange rates between participating currencies. Each member country agreed to keep its currency’s exchange rate within a narrow band against other member currencies.

2. **Promotion of Economic and Monetary Cooperation:** The mechanism was designed to facilitate closer economic and monetary cooperation among EU member states, paving the way for the eventual creation of a single currency, the euro.

The key features of the ERM included:

1. **Exchange Rate Bands:** Participating countries agreed to keep their currencies’ exchange rates within specified bands. These bands were expressed as percentage fluctuations around a central rate. Central rates were determined based on economic factors such as inflation, interest rates, and economic performance.

2. **Intervention Mechanisms:** Central banks of participating countries were allowed to intervene in the foreign exchange markets to stabilize their currencies. Intervention could involve buying or selling currencies to influence exchange rates.

3. **Adjustable Peg System:** The ERM operated on the principle of an adjustable peg system, where countries maintained a fixed exchange rate within a band but were allowed to adjust the central rate to reflect changing economic fundamentals.

4. **European Currency Unit (ECU):** The ECU was a basket currency created to serve as the unit of account for the ERM. It was composed of fixed amounts of each participating currency and acted as a reference point for exchange rate calculations.

The ERM faced challenges over the years, particularly during times of economic stress and divergence among member states. One notable event was the “Black Wednesday” in 1992 when the United Kingdom was forced to withdraw from the ERM due to unsustainable pressures on the British pound.

The adoption of the euro in 1999 marked a significant development in the European Union’s monetary integration. As part of this process, participating countries abandoned their individual currencies and adopted the euro, leading to the establishment of the Economic and Monetary Union (EMU). The ERM became less relevant after the introduction of the euro, as exchange rates between eurozone countries were fixed and no longer subject to fluctuations within the ERM.