The primary purpose of the foreign exchange market is to assist international trade and investment, by allowing businesses to convert one currency to another currency. For example, it permits a US business to import European goods and pay Euros, even though the business's income is in US dollars. It also supports speculation, and facilitates the carry trade, in which investors borrow low-yielding currencies and lend (invest in) high-yielding currencies, and which (it has been claimed) may lead to loss of competitiveness in some countries.
In a typical foreign exchange transaction a party purchases a quantity of one currency by paying a quantity of another currency. The modern foreign exchange market started forming during the 1970s when countries gradually switched to floating exchange rates from the previous exchange rate regime, which remained fixed as per the Bretton Woods system.
The foreign exchange market is unique because of its
- huge trading volume, leading to high liquidity
- geographical dispersion
- continuous operation: 24 hours a day except weekends, i.e. trading from 20:15 GMT on Sunday until 22:00 GMT Friday
- the variety of factors that affect exchange rates
- the low margins of relative profit compared with other markets of fixed income
- the use of leverage to enhance profit margins with respect to account size
As such, it has been referred to as the market closest to the ideal of perfect competition, notwithstanding market manipulation by central banks. According to the Bank for International Settlements, average daily turnover in global foreign exchange markets is estimated at $3.98 trillion, as of April 2007. $3.21 Trillion is accounted for in the world's main financial markets.
The $3.21 trillion break-down is as follows:
- $1.005 trillion in spot transactions
- $362 billion in outright forwards
- $1.714 trillion in foreign exchange swaps
- $129 billion estimated gaps in reporting
 Market size and liquidity
The foreign exchange market is the largest and most liquid financial market in the world. Traders include large banks, central banks, currency speculators, corporations, governments, and other financial institutions. The average daily volume in the global foreign exchange and related markets is continuously growing. Daily turnover was reported to be over US$3.2 trillion in April 2007 by the Bank for International Settlements.  Since then, the market has continued to grow. According to Euromoney's annual FX Poll, volumes grew a further 41% between 2007 and 2008.
Of the $3.98 trillion daily global turnover, trading in London accounted for around $1.36 trillion, or 34.1% of the total, making London by far the global center for foreign exchange. In second and third places respectively, trading in New York City accounted for 16.6%, and Tokyo accounted for 6.0%. In addition to "traditional" turnover, $2.1 trillion was traded in derivatives.
Several other developed countries also permit the trading of FX derivative products (like currency futures and options on currency futures) on their exchanges. All these developed countries already have fully convertible capital accounts. Most emerging countries do not permit FX derivative products on their exchanges in view of prevalent controls on the capital accounts. However, a few select emerging countries (e.g., Korea, South Africa, India—; ) have already successfully experimented with the currency futures exchanges, despite having some controls on the capital account.
FX futures volume has grown rapidly in recent years, and accounts for about 7% of the total foreign exchange market volume, according to The Wall Street Journal Europe (5/5/06, p. 20).
|5||Royal Bank of Scotland||6.50%|
Foreign exchange trading increased by 38% between April 2005 and April 2006 and has more than doubled since 2001. This is largely due to the growing importance of foreign exchange as an asset class and an increase in fund management assets, particularly of hedge funds and pension funds. The diverse selection of execution venues have made it easier for retail traders to trade in the foreign exchange market. In 2006, retail traders constituted over 2% of the whole FX market volumes with an average daily trade volume of over US$50-60 billion (see retail trading platforms).
Because foreign exchange is an OTC market where brokers/dealers negotiate directly with one another, there is no central exchange or clearing house. The biggest geographic trading centre is the UK, primarily London, which according to IFSL estimates has increased its share of global turnover in traditional transactions from 31.3% in April 2004 to 34.1% in April 2007. Due to London's dominance in the market, a particular currency's quoted price is usually the London market price. For instance, when the IMF calculates the value of its SDRs every day, they use the London market prices at noon that day.
The ten most active traders account for 77% of trading volume, according to the 2010 Euromoney FX survey. These large international banks continually provide the market with both bid (buy) and ask (sell) prices. The bid/ask spread is the difference between the price at which a bank or market maker will sell ("ask", or "offer") and the price at which a market taker will buy ("bid") from a wholesale or retail customer. The customer will buy from the market-maker at the higher "ask" price, and will sell at the lower "bid" price, thus giving up the "spread" as the cost of completing the trade. This spread is minimal for actively traded pairs of currencies, usually 0–3 pips. For example, the bid/ask quote of EURUSD might be 1.2200/1.2203 on a wholesale broker. Minimum trading size for most deals is usually 100,000 units of base currency, which is a standard "lot".
These spreads might not apply to retail customers at banks, which will routinely mark up the difference to say 1.2100/1.2300 for transfers, or say 1.2000/1.2400 for banknotes or travelers' checks. Spot prices at market makers vary, but on EURUSD are usually no more than 3 pips wide (i.e., 0.0003). Competition is greatly increased with larger transactions, and pip spreads shrink on the major pairs to as little as 1 to 2 pips.
 Market participants
Unlike a stock market, the foreign exchange market is divided into levels of access. At the top is the inter-bank market, which is made up of the largest commercial banks and securities dealers. Within the inter-bank market, spreads, which are the difference between the bid and ask prices, are razor sharp and usually unavailable, and not known to players outside the inner circle. The difference between the bid and ask prices widens (from 0-1 pip to 1-2 pips for some currencies such as the EUR). This is due to volume. If a trader can guarantee large numbers of transactions for large amounts, they can demand a smaller difference between the bid and ask price, which is referred to as a better spread. The levels of access that make up the foreign exchange market are determined by the size of the "line" (the amount of money with which they are trading). The top-tier inter-bank market accounts for 53% of all transactions. After that there are usually smaller banks, followed by large multi-national corporations (which need to hedge risk and pay employees in different countries), large hedge funds, and even some of the retail FX-metal market makers. According to Galati and Melvin, “Pension funds, insurance companies, mutual funds, and other institutional investors have played an increasingly important role in financial markets in general, and in FX markets in particular, since the early 2000s.” (2004) In addition, he notes, “Hedge funds have grown markedly over the 2001–2004 period in terms of both number and overall size” Central banks also participate in the foreign exchange market to align currencies to their economic needs.
The interbank market caters for both the majority of commercial turnover and large amounts of speculative trading every day. A large bank may trade billions of dollars daily. Some of this trading is undertaken on behalf of customers, but much is conducted by proprietary desks, trading for the bank's own account. Until recently, foreign exchange brokers did large amounts of business, facilitating interbank trading and matching anonymous counterparts for small fees. Today, however, much of this business has moved on to more efficient electronic systems. The broker squawk box lets traders listen in on ongoing interbank trading and is heard in most trading rooms, but turnover is noticeably smaller than just a few years ago.
 Commercial companies
An important part of this market comes from the financial activities of companies seeking foreign exchange to pay for goods or services. Commercial companies often trade fairly small amounts compared to those of banks or speculators, and their trades often have little short term impact on market rates. Nevertheless, trade flows are an important factor in the long-term direction of a currency's exchange rate. Some multinational companies can have an unpredictable impact when very large positions are covered due to exposures that are not widely known by other market participants.
 Central banks
National central banks play an important role in the foreign exchange markets. They try to control the money supply, inflation, and/or interest rates and often have official or unofficial target rates for their currencies. They can use their often substantial foreign exchange reserves to stabilize the market. Milton Friedman argued that the best stabilization strategy would be for central banks to buy when the exchange rate is too low, and to sell when the rate is too high—that is, to trade for a profit based on their more precise information. Nevertheless, the effectiveness of central bank "stabilizing speculation" is doubtful because central banks do not go bankrupt if they make large losses, like other traders would, and there is no convincing evidence that they do make a profit trading.
The mere expectation or rumor of central bank intervention might be enough to stabilize a currency, but aggressive intervention might be used several times each year in countries with a dirty float currency regime. Central banks do not always achieve their objectives. The combined resources of the market can easily overwhelm any central bank. Several scenarios of this nature were seen in the 1992–93 ERM collapse, and in more recent times in Southeast Asia.
 Hedge funds as speculators
About 70% to 90% of the foreign exchange transactions are speculative. In other words, the person or institution that bought or sold the currency has no plan to actually take delivery of the currency in the end; rather, they were solely speculating on the movement of that particular currency. Hedge funds have gained a reputation for aggressive currency speculation since 1996. They control billions of dollars of equity and may borrow billions more, and thus may overwhelm intervention by central banks to support almost any currency, if the economic fundamentals are in the hedge funds' favor.
 Investment management firms
Investment management firms (who typically manage large accounts on behalf of customers such as pension funds and endowments) use the foreign exchange market to facilitate transactions in foreign securities. For example, an investment manager bearing an international equity portfolio needs to purchase and sell several pairs of foreign currencies to pay for foreign securities purchases.
Some investment management firms also have more speculative specialist currency overlay operations, which manage clients' currency exposures with the aim of generating profits as well as limiting risk. Whilst the number of this type of specialist firms is quite small, many have a large value of assets under management (AUM), and hence can generate large trades.
 Retail foreign exchange brokers
Retail traders (individuals) constitute a growing segment of this market, both in size and importance. Currently, they participate indirectly through brokers or banks. Retail brokers, while largely controlled and regulated in the USA by the CFTC and NFA have in the past been subjected to periodic foreign exchange scams. To deal with the issue, the NFA and CFTC began (as of 2009) imposing stricter requirements, particularly in relation to the amount of Net Capitalization required of its members. As a result many of the smaller, and perhaps questionable brokers are now gone.
There are two main types of retail FX brokers offering the opportunity for speculative currency trading: brokers and dealers or market makers. Brokers serve as an agent of the customer in the broader FX market, by seeking the best price in the market for a retail order and dealing on behalf of the retail customer. They charge a commission or mark-up in addition to the price obtained in the market. Dealers or market makers, by contrast, typically act as principal in the transaction versus the retail customer, and quote a price they are willing to deal at—the customer has the choice whether or not to trade at that price.
In assessing the suitability of an FX trading service, the customer should consider the ramifications of whether the service provider is acting as principal or agent. When the service provider acts as agent, the customer is generally assured of a known cost above the best inter-dealer FX rate. When the service provider acts as principal, no commission is paid, but the price offered may not be the best available in the market—since the service provider is taking the other side of the transaction, a conflict of interest may occur.
 Non-bank foreign exchange companies
Non-bank foreign exchange companies offer currency exchange and international payments to private individuals and companies. These are also known as foreign exchange brokers but are distinct in that they do not offer speculative trading but currency exchange with payments. I.e., there is usually a physical delivery of currency to a bank account. Send Money Home offer an in-depth comparison into the services offered by all the major non-bank foreign exchange companies.
It is estimated that in the UK, 14% of currency transfers/payments are made via Foreign Exchange Companies. These companies' selling point is usually that they will offer better exchange rates or cheaper payments than the customer's bank. These companies differ from Money Transfer/Remittance Companies in that they generally offer higher-value services.
 Money transfer/remittance companies
Money transfer companies/remittance companies perform high-volume low-value transfers generally by economic migrants back to their home country. In 2007, the Aite Group estimated that there were $369 billion of remittances (an increase of 8% on the previous year). The four largest markets (India, China, Mexico and the Philippines) receive $95 billion. The largest and best known provider is Western Union with 345,000 agents globally followed by UAE Exchange & Financial Services Ltd.
 Trading characteristics
ISO 4217 code
| % daily share
|1||United States dollar||USD ($)||86.3%|
|3||Japanese yen||JPY (¥)||17.0%|
|4||Pound sterling||GBP (£)||15.0%|
|5||Swiss franc||CHF (Fr)||6.8%|
|6||Australian dollar||AUD ($)||6.7%|
|7||Canadian dollar||CAD ($)||4.2%|
|8-9||Swedish krona||SEK (kr)||2.8%|
|8-9||Hong Kong dollar||HKD ($)||2.8%|
|10||Norwegian krone||NOK (kr)||2.2%|
|11||New Zealand dollar||NZD ($)||1.9%|
|12||Mexican peso||MXN ($)||1.3%|
|13||Singapore dollar||SGD ($)||1.2%|
|14||South Korean won||KRW (₩)||1.1%|
There is no unified or centrally cleared market for the majority of FX trades, and there is very little cross-border regulation. Due to the over-the-counter (OTC) nature of currency markets, there are rather a number of interconnected marketplaces, where different currencies instruments are traded. This implies that there is not a single exchange rate but rather a number of different rates (prices), depending on what bank or market maker is trading, and where it is. In practice the rates are often very close, otherwise they could be exploited by arbitrageurs instantaneously. Due to London's dominance in the market, a particular currency's quoted price is usually the London market price. A joint venture of the Chicago Mercantile Exchange and Reuters, called Fxmarketspace opened in 2007 and aspired but failed to the role of a central market clearing mechanism.
The main trading center is London, but New York, Tokyo, Hong Kong and Singapore are all important centers as well. Banks throughout the world participate. Currency trading happens continuously throughout the day; as the Asian trading session ends, the European session begins, followed by the North American session and then back to the Asian session, excluding weekends.
Fluctuations in exchange rates are usually caused by actual monetary flows as well as by expectations of changes in monetary flows caused by changes in gross domestic product (GDP) growth, inflation (purchasing power parity theory), interest rates (interest rate parity, Domestic Fisher effect, International Fisher effect), budget and trade deficits or surpluses, large cross-border M&A deals and other macroeconomic conditions. Major news is released publicly, often on scheduled dates, so many people have access to the same news at the same time. However, the large banks have an important advantage; they can see their customers' order flow.
Currencies are traded against one another. Each currency pair thus constitutes an individual trading product and is traditionally noted XXXYYY or XXX/YYY, where XXX and YYY are the ISO 4217 international three-letter code of the currencies involved. The first currency (XXX) is the base currency that is quoted relative to the second currency (YYY), called the counter currency (or quote currency). For instance, the quotation EURUSD (EUR/USD) 1.5465 is the price of the euro expressed in US dollars, meaning 1 euro = 1.5465 dollars. Historically, the base currency was the stronger currency at the creation of the pair. However, when the euro was created, the European Central Bank mandated that it always be the base currency in any pairing.
The factors affecting XXX will affect both XXXYYY and XXXZZZ. This causes positive currency correlation between XXXYYY and XXXZZZ.
On the spot market, according to the BIS study, the most heavily traded products were:
- EURUSD: 27%
- USDJPY: 13%
- GBPUSD (also called cable): 12%
and the US currency was involved in 86.3% of transactions, followed by the euro (37.0%), the yen (17.0%), and sterling (15.0%) (see table). Volume percentages for all individual currencies should add up to 200%, as each transaction involves two currencies.
Trading in the euro has grown considerably since the currency's creation in January 1999, and how long the foreign exchange market will remain dollar-centered is open to debate. Until recently, trading the euro versus a non-European currency ZZZ would have usually involved two trades: EURUSD and USDZZZ. The exception to this is EURJPY, which is an established traded currency pair in the interbank spot market. As the dollar's value has eroded during 2008, interest in using the euro as reference currency for prices in commodities (such as oil), as well as a larger component of foreign reserves by banks, has increased dramatically. Transactions in the currencies of commodity-producing countries, such as AUD, NZD, CAD, have also increased.
 Determinants of FX rates
- (a) International parity conditions: Relative Purchasing Power Parity, interest rate parity, Domestic Fisher effect, International Fisher effect. Though to some extent the above theories provide logical explanation for the fluctuations in exchange rates, yet these theories falter as they are based on challengeable assumptions [e.g., free flow of goods, services and capital] which seldom hold true in the real world.
- (b) Balance of payments model (see exchange rate): This model, however, focuses largely on tradable goods and services, ignoring the increasing role of global capital flows. It failed to provide any explanation for continuous appreciation of dollar during 1980s and most part of 1990s in face of soaring US current account deficit.
- (c) Asset market model (see exchange rate): views currencies as an important asset class for constructing investment portfolios. Assets prices are influenced mostly by people’s willingness to hold the existing quantities of assets, which in turn depends on their expectations on the future worth of these assets. The asset market model of exchange rate determination states that “the exchange rate between two currencies represents the price that just balances the relative supplies of, and demand for, assets denominated in those currencies.”
None of the models developed so far succeed to explain FX rates levels and volatility in the longer time frames. For shorter time frames (less than a few days) algorithm can be devised to predict prices. Large and small institutions and professional individual traders have made consistent profits from it. It is understood from above models that many macroeconomic factors affect the exchange rates and in the end currency prices are a result of dual forces of demand and supply. The world's currency markets can be viewed as a huge melting pot: in a large and ever-changing mix of current events, supply and demand factors are constantly shifting, and the price of one currency in relation to another shifts accordingly. No other market encompasses (and distills) as much of what is going on in the world at any given time as foreign exchange.
Supply and demand for any given currency, and thus its value, are not influenced by any single element, but rather by several. These elements generally fall into three categories: economic factors, political conditions and market psychology.
 Economic factors
- Economic policy comprises government fiscal policy (budget/spending practices) and monetary policy (the means by which a government's central bank influences the supply and "cost" of money, which is reflected by the level of interest rates).
- Government budget deficits or surpluses: The market usually reacts negatively to widening government budget deficits, and positively to narrowing budget deficits. The impact is reflected in the value of a country's currency.
- Balance of trade levels and trends: The trade flow between countries illustrates the demand for goods and services, which in turn indicates demand for a country's currency to conduct trade. Surpluses and deficits in trade of goods and services reflect the competitiveness of a nation's economy. For example, trade deficits may have a negative impact on a nation's currency.
- Inflation levels and trends: Typically a currency will lose value if there is a high level of inflation in the country or if inflation levels are perceived to be rising. This is because inflation erodes purchasing power, thus demand, for that particular currency. However, a currency may sometimes strengthen when inflation rises because of expectations that the central bank will raise short-term interest rates to combat rising inflation.
- Economic growth and health: Reports such as GDP, employment levels, retail sales, capacity utilization and others, detail the levels of a country's economic growth and health. Generally, the more healthy and robust a country's economy, the better its currency will perform, and the more demand for it there will be.
- Productivity of an economy: Increasing productivity in an economy should positively influence the value of its currency. Its effects are more prominent if the increase is in the traded sector .
 Political conditions
Internal, regional, and international political conditions and events can have a profound effect on currency markets.
All exchange rates are susceptible to political instability and anticipations about the new ruling party. Political upheaval and instability can have a negative impact on a nation's economy. For example, destabilization of coalition governments in Pakistan and Thailand can negatively affect the value of their currencies. Similarly, in a country experiencing financial difficulties, the rise of a political faction that is perceived to be fiscally responsible can have the opposite effect. Also, events in one country in a region may spur positive/negative interest in a neighboring country and, in the process, affect its currency.
 Market psychology
Market psychology and trader perceptions influence the foreign exchange market in a variety of ways:
- Flights to quality: Unsettling international events can lead to a "flight to quality," with investors seeking a "safe haven." There will be a greater demand, thus a higher price, for currencies perceived as stronger over their relatively weaker counterparts. The U.S. dollar, Swiss franc and gold have been traditional safe havens during times of political or economic uncertainty.
- Long-term trends: Currency markets often move in visible long-term trends. Although currencies do not have an annual growing season like physical commodities, business cycles do make themselves felt. Cycle analysis looks at longer-term price trends that may rise from economic or political trends.
- "Buy the rumor, sell the fact": This market truism can apply to many currency situations. It is the tendency for the price of a currency to reflect the impact of a particular action before it occurs and, when the anticipated event comes to pass, react in exactly the opposite direction. This may also be referred to as a market being "oversold" or "overbought". To buy the rumor or sell the fact can also be an example of the cognitive bias known as anchoring, when investors focus too much on the relevance of outside events to currency prices.
- Economic numbers: While economic numbers can certainly reflect economic policy, some reports and numbers take on a talisman-like effect: the number itself becomes important to market psychology and may have an immediate impact on short-term market moves. "What to watch" can change over time. In recent years, for example, money supply, employment, trade balance figures and inflation numbers have all taken turns in the spotlight.
- Technical trading considerations: As in other markets, the accumulated price movements in a currency pair such as EUR/USD can form apparent patterns that traders may attempt to use. Many traders study price charts in order to identify such patterns.
 Algorithmic trading in foreign exchange
Electronic trading is growing in the FX market, and algorithmic trading is becoming much more common. According to financial consultancy Celent estimates, by 2008 up to 25% of all trades by volume will be executed using algorithm, up from about 18% in 2005.
 Financial instruments
A spot transaction is a two-day delivery transaction (except in the case of trades between the US Dollar, Canadian Dollar, Turkish Lira and Russian Ruble, which settle the next business day), as opposed to the futures contracts, which are usually three months. This trade represents a “direct exchange” between two currencies, has the shortest time frame, involves cash rather than a contract; and interest is not included in the agreed-upon transaction.
One way to deal with the foreign exchange risk is to engage in a forward transaction. In this transaction, money does not actually change hands until some agreed upon future date. A buyer and seller agree on an exchange rate for any date in the future, and the transaction occurs on that date, regardless of what the market rates are then. The duration of the trade can be a one day, a few days, months or years. Usually the date is decided by both parties. and foreward contract is a negotiated and agreement between two parties
Foreign currency futures are exchange traded forward transactions with standard contract sizes and maturity dates — for example, $1000 for next November at an agreed rate ,. Futures are standardized and are usually traded on an exchange created for this purpose. The average contract length is roughly 3 months. Futures contracts are usually inclusive of any interest amounts.
The most common type of forward transaction is the currency swap. In a swap, two parties exchange currencies for a certain length of time and agree to reverse the transaction at a later date. These are not standardized contracts and are not traded through an exchange.
A foreign exchange option (commonly shortened to just FX option) is a derivative where the owner has the right but not the obligation to exchange money denominated in one currency into another currency at a pre-agreed exchange rate on a specified date. The FX options market is the deepest, largest and most liquid market for options of any kind in the world..
Controversy about currency speculators and their effect on currency devaluations and national economies recurs regularly. Nevertheless, economists including Milton Friedman have argued that speculators ultimately are a stabilizing influence on the market and perform the important function of providing a market for hedgers and transferring risk from those people who don't wish to bear it, to those who do. Other economists such as Joseph Stiglitz consider this argument to be based more on politics and a free market philosophy than on economics.
Large hedge funds and other well capitalized "position traders" are the main professional speculators. According to some economists, individual traders could act as "noise traders" and have a more destabilizing role than larger and better informed actors .
Currency speculation is considered a highly suspect activity in many countries.[where?] While investment in traditional financial instruments like bonds or stocks often is considered to contribute positively to economic growth by providing capital, currency speculation does not; according to this view, it is simply gambling that often interferes with economic policy. For example, in 1992, currency speculation forced the Central Bank of Sweden to raise interest rates for a few days to 500% per annum, and later to devalue the krona. Former Malaysian Prime Minister Mahathir Mohamad is one well known proponent of this view. He blamed the devaluation of the Malaysian ringgit in 1997 on George Soros and other speculators.
Gregory J. Millman reports on an opposing view, comparing speculators to "vigilantes" who simply help "enforce" international agreements and anticipate the effects of basic economic "laws" in order to profit.
In this view, countries may develop unsustainable financial bubbles or otherwise mishandle their national economies, and foreign exchange speculators made the inevitable collapse happen sooner. A relatively quick collapse might even be preferable to continued economic mishandling, followed by an eventual, larger, collapse. Mahathir Mohamad and other critics of speculation are viewed as trying to deflect the blame from themselves for having caused the unsustainable economic conditions.
 Risk Aversion in Forex
Risk Aversion in the Forex is a kind of trading behavior exhibited by the foreign exchange market when a potentially adverse event happens which may affect market conditions.
In the context of the forex market, traders liquidate their positions in various currencies to take up positions in safe haven currencies, such as the US Dollar.
Sometimes the choice of a safe haven currency is more of a choice based on prevailing sentiments rather than one of economic statistics.
An example would be the Financial Crisis of 2008. The value of equities across world fell while the US Dollar strengthened.( See Fig.1 ) This happened despite the strong focus of the crisis in the USA.