This article investigated the possible costs of disinflation experienced in Colombia from 1998 to 2003, using a structural VAR model with short- and long-term restrictions based on the Buiter-Miller model (1982). This analyses the effects of decelerating monetary growth on the real interest rate, the real exchange rate, production and prices. Innovation accounting led to the conclusion that shocks to the real interest rate and a growing monetary base were the main causes of disinflation.