High real interest rates have been observed in many countries for several months after the adoption of disinflation programs. While they may reflect primarily a liquidity crunch, high ex-post real interest rates can also be explained in terms of an ex post error in inflation expectations that reflects a lack of credibility of the low-inflation policy. The latter hypothesis is tested using data for Argentina, Israel, and Mexico during the implementation of the stabilization programs in the mid-1980s.