money-market condtions. These findings leave open the possibility that sterilised foreign exchange market intervention has significant but short-lived exchange rate effects that disappear within a month. Sterilised intervention in the portfolio balance framework is also studied by Rogoff (1984). He employs weekly data for the Canadian dollar – US dollar exchange rate and other relevant weekly data to estimate the portfolio balance model, asserting that previous studies are based on monthly or quarterly data that contain limited information about the very short-run effects of intervention. The sample period spans from March 1973 through December 1980. Despitethe use of higher frequency data and a little more advanced estimation procedure the results are not supportive of the existence of a portfolio balance effect in which the portfolio balance variables appear with statistically significant coefficients of