The multilateral real exchange rates of major industrial countries often contain deterministic time trends. This note develops a simple stochastic model of a small open economy with a deterministically trending real exchange rate. Real exchange rate trends are caused by differential productivity growth in tradables and nontradables. Although the model assumes complete price flexibility, it can produce a correlation between the real exchange rate and the international real interest-rate differential similar to the one that arises in sticky-price overshooting models dominated by monetary shocks.