Résumé : We assess the perception of professional forecasters regarding the effectiveness of unconventionalmonetary policy measures undertaken by the U.S. Federal Reserve after the collapse of LehmanBrothers. Using individual survey data, we analyse the changes in forecasting of bond yields aroundthe announcement and implementation dates of non-standard monetary policies. The resultsindicate that bond yields are expected to drop significantly for at least one year after theannouncement and the implementation of accommodative policies.