Using daily data on foreign exchange interventions of both the Bundesbank and the Fed we provide further evidence that central banks earn profits with interventions and that technical trading rules are unusually profitable on days on which interventions take place. We argue that what lies at the root of these seemingly contradictory results is that (a) intervention profits and trading rule profitability are measured over different horizons and (b) after interventions, exchange rates tend to move contrary to central banks' intentions in the short run, but in agreement with their intentions in the long run.