Understanding the overall structure of the foreign exchange market allows for a deeper examination of the spot FX market, along with the roles and influence of its participants. Historically, the forex market was reserved exclusively for well-capitalized institutions; it was not accessible to everyone. With the advent of the internet, access has expanded significantly, making it essential to understand the players operating within the market.

1. Super Banks

Leading the list of forex market participants, super banks serve several essential functions:

• Setting Exchange Rates: Super banks establish benchmark rates for major currencies, a critical factor driving overall forex market flow.

• Creating Bid-Ask Spreads: They quote bid/ask spreads based on supply and demand dynamics across currency pairs. 

• The Interbank Market: By trading directly with one another, super banks form the interbank market, which accounts for the vast majority of global FX volume.

Super banks are sometimes referred to as "market flow monsters" because they control massive order flow. Handling massive transaction volume daily, their market influence is undeniable.

2. Large Commercial Corporations

Major commercial corporations leading consumer and industrial sectors also exert significant influence on the forex market. These companies participate primarily to facilitate cross-border commercial transactions, converting capital into destination currencies to execute large-scale purchases.

Corporate participation extends beyond routine trade to cross-border mergers and acquisitions (M&A). When these M&A transactions occur, markets often see pronounced moves. For instance, when a corporation acquires an overseas firm, the resulting shift in currency supply and demand directly impacts exchange rates.

As a result, large commercial corporations not only transact substantial capital, but also serve as key drivers of overall market volatility.

3. Governments and Central Banks

Beyond corporations, key market participants include governments and central banks. Both impact market structure in distinct ways.

Governments:

• Daily Operations: Governments use the forex market for routine international transactions and diplomatic expenses.

• Foreign Reserve Management: Sovereign entities hold and manage foreign currency reserves to support economic stability, requiring ongoing FX market operations.

• International Trade Settlement: Governments facilitate settlements for sovereign international trade obligations through the FX market.

Central Banks:

• Interest Rate Policy: Central banks manage interest rate policy to maintain macroeconomic stability. Rate adjustments target inflation control and economic growth, which directly drive FX valuations.

• Currency Intervention: In select scenarios, central banks intervene directly in the FX market to stabilize domestic currency value, curbing excessive volatility to preserve financial stability.

Through monetary and fiscal policy, governments and central banks exert direct control over the foreign exchange market. Their policy decisions dictate overall market stability, currency volatility, and macroeconomic trajectories.

4. Forex Speculators and Traders

Finally, there are forex speculators and traders, whose sole objective in the market is generating profit.

By closely tracking price action, they buy currencies identified as undervalued and hold positions until they can exit profitably. 

Because this segment trades without commercial trade constraints, it accounts for roughly 90% of total forex volume, driving overall market liquidity, volatility, and price discovery.