This paper examines the structure of Japanese import and export behavior for semiconductors by analyzing four pertinent quarterly series, namely; import prices of integrated circuits (ICs), real imports of semiconductors, and wholesale and export prices of ICs in Japan during the 1980:1- 1996:3 period. Real monthly imports of integrated circuits from 1988:1 to 1996:7 are also examined. The methodology used is that of Perron (1989) wherein he tests the null and alternative hypotheses of a unit root or `trend-stationary` series, respectively, in the presence of possible slope and/or level shifts. The results indicate that real imports of semiconductors appear to have a change in slope in 1986:3, when the first Semiconductor Trade Agreement was signed. In the more limited series of monthly data for imports of integrated circuits, there appears to be an increase in its trend at the start of the second agreement in 1992. Wholesale prices, import prices and exports prices cannot reject the unit-root null and do not show signs of structural break, though this may be due to the limitations of the procedure.