The Fisher hypothesis claims that changes in the expected inflation ra
te will be fully reflected in nominal interest rates, and hence that r
eal interest rates will remain constant over time. Evidence with Austr
alian data from 1965 to 1990 suggests that the Fisher effect does not
hold in the long-run. Analysis is performed using recently developed e
conometric techniques which take account of possible nonstationarity i
n the data. Attention is also given to the effects of financial market
deregulation on interest rates.