Ladd and Martin's hedonic pricing model is extended to include the interactive effect of noncontracted characteristics on the value of contracted characteristics. Marginal values of wheat protein in the Japanese import market are estimated using the interactive effects of noncontracted dough/flour characteristics typically proxied by protein. Protein value is linked positively to farinograph stability, a prime factor in blending different flours. Three high protein wheats maintained about the same marginal value of protein. The marginal value for the two low protein wheats appear more end-use dependant. They varied in a $2.00/ton range depending on protein absorption, stability, and extensibility.