Open market operations constitute a key element of the ECB's range of policy instruments. The paper compares their application within the Eurosystem and selected EU candidate countries (the Czech Republic, Hungary and Poland), indicating the main areas where harmonisation is necessary.

There is no explicit requirement for the central banks of the aspiring countries to accomplish a full harmonisation of policy tools by a certain date at either the pre-accesion or even membership stage. Nevertheless, the adjustment of procedures and technical parameters has to be finalised early enough to allow the national central and commercial banks a swift transition - as soon as they assume the euro - into the Eurosystem with its joint monetary policy.

The candidate countries tend to support the view that their EU accession should be quickly followed by their accession to the euro zone (two years after joining the EU at the earliest). Most central banks concerned have already started preparations for the EU membership. These preparations involve, on the one hand, the efforts to satisfy the Maastricht criteria of macroeconomic performance, and on the other, harmonisation of the operational issues, e.g. those involving monetary policy instruments.