A stock exchange is a form of exchange which provides services for stock brokers and traders to trade stocks, bonds, and other securities. Stock exchanges also provide facilities for issue and redemption of securities and other financial instruments, and capital events including the payment of income and dividends. Securities traded on a stock exchange include shares issued by companies, unit trusts, derivatives, pooled investment products and bonds.

To be able to trade a security on a certain stock exchange, it must be listed there. Usually, there is a central location at least for record keeping, but trade is increasingly less linked to such a physical place, as modern markets are electronic networks, which gives them advantages of increased speed and reduced cost of transactions. Trade on an exchange is by members only.

The initial offering of stocks and bonds to investors is by definition done in the primary market and subsequent trading is done in the secondary market. A stock exchange is often the most important component of a stock market. Supply and demand in stock markets are driven by various factors that, as in all free markets, affect the price of stocks (see stock valuation).

The Irish Stock Exchange (ISE) (Irish: Stocmhalartán na hÉireann) is Ireland's only stock exchange and has been in existence since 1793. It is an Irish private company limited by guarantee. It was first recognised by legislation in 1799 when the Irish Parliament passed the Stock Exchange (Dublin) Act. At different periods in its history, the ISE included a number of regional exchanges, including the Cork and Dublin exchanges. In 1973, the Irish exchange merged with the other British and Irish stock exchanges becoming part of the International Stock Exchange of Great Britain and Ireland (now called the London Stock Exchange).Between 1973 and 1986 there were no new company listings.

In 1995, it became independent again and since then has expanded internationally and established itself as a global listing centre for international fund and debt securities.

The Irish Stock Exchange operates three markets:

The Main Securities Market (MSM), the principal market for Irish and overseas companies, which admits a wide range of security types such as shares, bonds and funds to listing and trading. The Main Securities Market is a regulated market as defined by Markets in Financial Instruments Directive (MIFID). It is the principal market of the ISE for larger, more established companies - Irish and international - from a broad range of industry sectors including financial services, building, oil and gas, utilities and food.