This paper empirically determines why, during the 1990s, inflation in Canada was consistently more stable than predicted by the fixed-coefficients Phillips curve. A time-varying-coefficient model, where all the parameters adjust simultaneously, shows that the behaviour of expectations was probably a major contributing factor. A decrease in the value of the coefficient on the first difference of the output gap also seems to have influenced the observed pattern of inflation. Finally, pass-through of relative price shocks into domestic prices is shown to have been low since 1983.