How to trade at Athens Stock Exchange (ASE)
Saxo Bank offers direct access to Athens Stock Exchange. Interactive Brokers is your next best bet, and as you probably already noticed, they do not have a free platform. They are open to US and non-US citizens. Although they do not currently have direct exposure to individual companies on the Athens Stock Exchange, the various european exchanges they do provide direct market access for will give a lot of exposure. There are a few Greek companies that trade on non-Greek stock exchanges, if you want exposure. There are also Greek ETFs which bundle several companies together or try to replicate Greek company indices.
Try Google Finance Screener ; you will be able to filter for NASDAQ and NYSE exchanges. "Very simple. You open an account with a broker who will do the trades for you. Then you give the broker orders to buy and sell (and the money to pay for the purchases). That's it. In the old days, you would call on the phone (remember, in all the movies, ""Sell, sell!!!!""? That's how), now every decent broker has an online trading platform. If you don't want to have ""additional value"" and just trade - there are many online discount brokers (ETrade, ScotTrade, TD Ameritrade, and others) who offer pretty cheap trades and provide decent services and access to information. For more fees, you can also get advices and professional management where an investment manager will make the decisions for you (if you have several millions to invest, that is). After you open an account and login, you'll find a big green (usually) button which says ""BUY"". Stocks are traded on exchanges. For example the NYSE and the NASDAQ are the most common US exchanges (there's another one called ""pink sheets"", but its a different kind of animal), there are also stock exchanges in Europe (notably London, Frankfurt, Paris, Moscow) and Asia (notably Hong Kong, Shanghai, Tokyo). Many trading platforms (ETrade, that I use, for example) allow investing on some of those as well." When you are placing an order with an online broker you should already know what exchange or exchanges that stock trades on. For example if you look up under Yahoo Finance: Notice how News Corp is traded both on the ASX and the Nasdaq. The difference is the shares traded on the ASX have the extension .AX, that is how you know the difference between them. When you are putting orders in with your online broker you will need to select the exchange you wish your order to go to (if your broker allows trading on multiple exchanges). So you should always know which exchange your order goes to. As far as I know, with ADRs you're essentially trading by proxy -- a depository bank is holding the actual stock certificate, and must provide you with the actual stock on demand. The one thing that is different is that in the event that the ADR is terminated (which sometimes happens with mergers), you have a limited period of time to sell the shares -- otherwise, you get the actual foreign stock that you may or may not be able to trade without transferring to a different broker. "A ""stock price"" is nothing but the price at which some shares of that stock were sold on an exchange from someone willing to sell those shares at that price (or more) to someone willing to buy them at that price (or less). Pretty much every question about how stock prices work is answered by the paragraph above, which an astonishingly large number of people don't seem to be aware of. So there is no explicit ""tracking"" mechanism at all. Just people buying and selling, and if the current going price on two exchanges differ, then that is an opportunity for someone to make money by buying on one exchange and selling on the other - until the prices are close enough that the fees and overhead make that activity unprofitable. This is called ""arbitrage"" and a common activity of investment banks or (more recently) hedge funds and specialized trading firms spun off by said banks due to regulation." Off the top of my head, a broker: While there are stock exchanges that offer direct market access (DMA), they (nearly) always want a broker as well to back the first two points I made.  In that case the broker merely routes your orders directly to the exchange and acts as a custodian, but of course the details heavily depend on the exchange you're talking about. This might give you some insight: Direct Market Access - London Stock Exchange The easiest route for you to go down will be to consult wikipedia, which will provide a comprehensive list of all US stock exchanges (there are plenty more than the ones you list!). Then visit the websites for those that are of interest to you, where you will find a list of holiday dates along with the trading schedule for specific products and the settlement dates where relevant. In answer to the other part of your question, yes, a stock can trade on multiple exchanges. Typically (unless you instruct otherwise), your broker will route your order to the exchange where it can be matched at the most favorable price to you at that time. To start trading at a minimum you need 3 things; Bank Account: This again is not must, but most preferred to transact. Quite a few broker would insist on this. Demat Account: This is must as all shares on NSE are held electronically. The custodians are CSDL or NSDL both Government entities. These don't offer services directly to customer, but via other financial institutions like Banks and Large Brokers. Broker Account: This is required to buy or sell securities. If you are only buying in IPO, this is not required as one can directly participate in IPO and Broker is not involved. However if you want to buy and sell on NSE you would need a broker account. Quite a few financial institutes offer all 3 services or 2 services [Demat/Broker]. The fee structure and online service etc are differentiators. You can take a look at options and decide the best one to use. A stock exchange is a marketplace where people can bring their goods [shares] to be traded. There are certain rules. Stock Exchange does not own any shares of the companies that are trading in.  The list of who owns with stock is with the registrar of each company. The electronic shares are held by a Financial Institution [Securities Depository]. So even if the exchange itself goes down, you still hold the same shares as you had before it went down. One would now have to find ways to trade these shares ... possibly via other stock exchange. This leaves the question of inflight transactions, which again would be recorded and available. Think of it similar to eBay. What happens when eBay goes bankrupt? Nothing much, all the seller still have their goods with them. All the buyers who had purchased good before have it when them ... so the question remains on inflight goods where the buyer has paid the seller and not yet received shipments ... Wikipedia is your friend: http://en.wikipedia.org/wiki/List_of_stock_exchanges You can check whether the company whose stock you want to buy is present on an european market. For instance this is the case for Apple at Frankfurt. If I buy VUSA from one exchange, can I sell it in a different exchange, assuming my brokerage account lets me trade in both exchanges? Or is it somehow tied to the exchange I bought it from? This doesn't happen for all securities and between all stock exchanges. So that is dependent on broker and country. I checked for VUSA with Selftrade. They categorically refused allowing me to trade in VUSA in different exchanges. I can only buy and sell in same currency only, albeit sell(buy) in the same exchange where I buy(sell) from. Should be the same behaviour for all brokers for us mere mortals, if you are a bank or a millionaire than that might be a different question.  The VUSA you quote is quoted in GBP in LSE and in EUR in AEX, and the ETF has been created by an Irish entity and has an Irish ISIN.  As Chris mentioned below, happens between US and Canadian exchanges, but not sure it happens across all exchanges. You cannot deal in inter-listed stocks in LSE and NYSE. Since it's the same asset, its value should not vary across exchanges once you compensate for exchange rates, right? Yes, else it opens up itself for arbitrage (profit without any risk) which everybody wants. So even if any such instance occurs, either people will exploit it to make the arbitrage profit zero (security reflects the equilibrium price) or the profit from such transaction is so less, compared with the effort involved, that people will tend to ignore it. Anyways arbitrage profit is very difficult to garner nowadays, considering the super computers at work in the market who exploit these discrepancies, the moment they see them and bring the security right to the zero arbitrage profit point. If there's no currency risk because of #2, what other factors should I consider when choosing an exchange to trade in? Liquidity? Something else? Time difference, by the time you wake up to trade in Japan, the Japanese markets would have closed. Tax implications across multiple continents. Law of the land, providing protection to investors. Finding a broker dealing in markets you want to explore or dealing with multiple brokers. Regulatory headaches. You or the broker place an order to buy the share with the stock exchange. There has to be a matching sell order by someone.  Once a match is made, you pay the money and get the share. "There are a number of choices: I prefer Dilip's response ""Have you tried asking etrade?"" No offense, but questions about how a particular broker handles certain situations are best asked of the broker.  Last - one should never enter into any trade (especially options trades) without understanding the process in advance. I hope you are asking this before trading." I have done this last year. Just open an account with an online brocker and buy a couple of Apple shares (6 I think, for 190$ each or something like that :) ). If this is just to test how stock exchange works, I think this is a good idea. I am also in Europe (France), and you'r right the charge to buy on NasDaq are quite expensive but still reasonnable. Hope this helps.