1) THE CURRENT monetary control mechanism in South Africa, which was implemented on the recommendations of the De Kock Commission (RSA, 1985), is one regulating the cost, rather than the availability of funds at the discount window. As some of the changes associated with the new mechanism were introduced during the early 1980s, and seeing that they were fully in line with the findings of the Commission in 1985, it can be argued that the current period in monetary control started with the appointment of Dr De Kock as governor of the Reserve Bank in 1981. These changes, together with the subsequent appearance of the De Kock Commission's report, coincided with several publications*(2) on the theory of monetary control. After 1986, however, this discipline did not receive the same attention*(3). The new market orientated policy, combined with the above cost of funds-approach, attached great importance to the role of Bank Rate as monetary control instrument. This is illustrated by the independent determination of the Bank Rate since 1983, which is in contrast to the system of a penalty margin above market discount rates before this time. The objective of this change was to strengthen the role of the Bank Rate and to make it instrumental in exercising a greater degree of influence over market rates. Being declared market related, Bank Rate from this time has been set at levels which are seen by the Reserve Bank as appropriate in the light of trends in the financial markets, the business cycle, growth in the money supply, gold and foreign exchange reserves, inflation and the exchange rate. Having opted for the above approach in monetary control*(4), the Reserve Bank requires not only effective influence over the levels of market interest rates, but also the ability to create an environment of general stability in the financial markets. The latter refers more specifically to the avoidance of undue short-term fluctuations from the general cyclical course over time, to which all interest rates are subject. This points to a need for empirical work, firstly on the degree of stability achieved in market interest rates, and secondly