Another issue is distribution of producer benefits among producers. Even if we can be assured that producers as a whole would benefit, those who do not adopt the new technology will not gain and may even be made worse off if the adoption by others leads to price reductions. The introduction of international trade is a str aightforward elaboration of the simple model, from which we can obtain measures of welfare impacts for different spatial or market aggregates. It becomes slightly more complicated when we allow in the same model for technological spillovers.