Securities financing is usually defined as a method of financing credit using securities. In a narrow sense, it is a method through which credit is provided with collateral of securities however, it usually covers also an extensive range of transactions concerning issuance, collateral and underwriting of various kinds of bonds, stocks, etc. in financial markets. Securities financing, therefore, not only promotes transaction of securities but also enables the government and firms to initiate or increase issuance of their public and private bonds and stocks to finance their requirements of long-term capital. Securities financing is especially an important method to finance necessary domestic capital for economic development in Korea. Here a brief description of the situation in Korea seems to be noteworthy. The Korean economy in the past years has grown rapidly with accompanying increase in the business volume and capital. Increase in business capital in Korea, however, has not been supported by the services of organized capital market, but rather by the active support of banks or government and by successful inflows of foreign loans, both commercial and public. According to the recent announcement of the Economic Planning Board, inducement of foreign capital, commercial and public loans and foreigners` direct investment, amounted to about 3 billion dollars, as of the end of December 1970. An analysis of the financial structure of business firms by the Bank of Korea has shown an equity capital ratio of 25 per cent of big corporations as of the end of December 1970. The majority of business firms still suffer from a chronic shortage of capital, long-term and short-term, and high debt-equity ratio. Owing to this situation, the future growth potential will be repressed. To carry out successfully the economic development plan in Korea, a huge amount of domestic and foreign capital must be financed rationally. If Korea cannot raise appropriate amounts of domestic capital from an organized capital market, foreign capital cannot be raised or utilized effectively. However, the Korean capital market is characterized by a limited supply of securities and inadequate demand for them. Therefore, the government is now striving for development of the capital market by considering measures to increase the supply of securities in the market and the demand to absorb the supply. Expansion of securities financing is considered to be one of the most efficient ways to increase the supply and demand of securities and to foster a capital market in an economy. Observing the recent past in Korean it is not difficult, however, to judge that the role of financial markets in connection with securities financing is extremely insignificant when the amount transacted in this way is compared with that of foreign capital investment, government loan and other similar credit arrangement. Moreover, it is also important to note that no foreign capital investment is undertaken in securities financing. Hence, the potential role of securities financing in Korea, when it is properly promoted, will be enlarged and will contribute to better results than any other method of credit arrangement. In this paper, the types of securities financing, in the limited sense that securities financing is a method based on the collateralization of securities in financing, were classified into the following three categories. 1) Securities underwriting financing as a fundamental transaction in a primary (issue) market, 2) Securities investment financing in a secondary (circulation) market, and 3) General securities financing by collateralization. The development process of securities financing was divided into three different types as categorized above. For convenience the development process is also chronologically divided into two periods: (1) From the establishment of the securities market in 1956 to the great securities price fluctuation in 1962 and (2) From 1962 to present.