August 9, 1995 Gordon Thiessen, Governor of the Bank of Canada, delivered the HERMES-Glendon Lecture at York University, Toronto, in March 1995. The speech focussed on the interrelationships of uncertainty and the transmission of monetary policy to the economy. It looked at how the various types of uncertainty influence the behaviour of economic actors, and at how uncertainty affects the transmission of monetary policy through the economy. The first part of the lecture outlines the Bank of Canada's view of the transmission mechanism, with considerable attention paid to the role of uncertainty. In the second part, the various ways in which the Bank has tried to reduce uncertainty are discussed. The various kinds of uncertainty that impinge on the economy and on the policy process are addressed.