The purpose of this paper is to explain empirical observations concerning t
he impact of exchange rate changes on industrial prices. As exchange rates
change the pass-through into industrial prices is often incomplete and some
times it goes into the 'wrong' direction, i.e. the prices in the depreciati
ng country decrease while those in the appreciating country increase. The l
atter is called 'perverse pass-through'. The usual context for such observa
tions is one of segmented markets and imperfect competition. We consider th
e simplest model with these characteristics: Two duopolistic firms which bo
th operate in two countries. The markets of the two countries are separate
and each of the firms produces its good in one of these countries. We study
the effect of an exchange rate change on the prices in each country and on
the level of sales and of profits of each of the firms. When strong restri
ctions such as constant marginal costs are imposed, prices move in the 'rig
ht' direction in response to an exchange rate change. However, with general
cost and demand structures, even in this simple model, it is possible for
prices in both countries to move in 'perverse' directions. (C) 1999 Elsevie
r Science B.V. All rights reserved.