Perron's test, Johansen cointegration analysis, and a vector error-correction (VEC) model are used to identify structural change, as well as to examine price dynamics in the U. S. and Canadian hard red spring (HRS) and durum wheat markets. It is found that, due to the U. S. Export Enhancement Program (EEP), price instability experienced in June 1986 has resulted in structural changes for Canadian HRS and durum prices. We also find that Canadian prices have significant effects on the determination of the U. S. prices in the North American wheat market.