Secondary markets, or secondary financial markets, trade existing securities (previously owned shares of stocks, bonds, and other financial assets). Secondary markets consist of both organized exchanges, such as the New York Stock Exchange, and over-the-counter or electronic markets, such as NASDAQ: secondary markets consist of markets in which existing securities are traded.

Organized stock exchanges: Organized stock exchanges are markets that are used to facilitate the trading of financial instruments. The main organized stock exchanges are the New York Stock Exchange and the American Stock Exchange. There are also regional stock exchanges, such as the Pacific, Chicago, Philadelphia, Cincinnati, Intermountain, Spokane, and Boston Stock Exchanges, but these stock exchanges are very small.

The largest stock exchange in the United States is the New York Stock Exchange. This stock exchange is more than two hundred years old, and it is still limited to 1,366 seats: the same number of seats it has had since 1953. The New York Stock Exchange includes over 3,000 listed companies. Generally, 80 percent of the daily trading volume in the United States is done on the New York Stock Exchange.

Over-the-counter (OTC) market: The OTC market is an electronic network of dealers that allows investors to execute trades without going through specialists or intermediaries. That is, there is no single physical location (exchange) where stocks are traded, rather these trades are executed through the National Association of Securities Dealer Automated Quotation System (NASDAQ) which links various dealers and brokers through a computer or telephone based system. Usually the bigger companies are traded on an exchange rather than an OTC.  These trades are also executed through the National Market System, a system under the sponsorship of the National Association of Securities Dealers (NASD), which trades stocks of specific sizes, profitability, and trading requirements. NASD also trades “pink sheets,” or lists of small companies not listed on any exchange; these stocks are traded by brokers through a network of phone and computer systems and may be significantly more risky.

Secondary bond markets: An organized exchange for individual retail investors to trade bonds does not exist. This may be because there is little demand for bonds among individual investors; this may also be because the transaction costs to trade bonds are so small. Generally, individuals must work with a broker who buys or sells bonds through a bond dealer.

Government bond trading: Government bond trading is dominated by investment houses, commercial banks, and the Federal Reserve. Some bonds, such as Series EE and I Bonds and some Treasury securities, can be purchased directly over the Internet at www.treasurydirect.gov.

International stock markets: There are domestic stock exchanges in the developed countries and in many of the emerging or developing countries.] Most nations have securities exchanges; these markets  trade more than $25 trillion in assets. In the U.S. stock markets  investors can often trade American Depository Receipts (ADRs), which are receipts for -shares that are held on deposit by foreign banks and represent ownership of companies which have their primary listing on exchanges outside the United States.-. Buying an ADR is very similar to buying the underlying domestic share from their home market, except you get your dividends in U.S. dollars and your annual report information in English. Another way to invest in international shares is to invest in mutual funds: many mutual funds invest internationally.