Extract: This study formulates a dynamic econometric model of the U.S. processing tomato industry. The behavioral elements of the model consist of processed product demand equations facing processors, processor market allocation equations, raw product demand equations facing growers, and grower supply equations. The processed product demand and market allocation equations involve a block of five sets of simultaneously determined equations - one set for each of the five major commodity forms. The California processor raw product demand and grower supply equations form another block of simultaneous equations. The Midwest and East grower price and acreage equations are sequentially linked to California adjustments through a price relationship. The estimates of supply and demand equations, which are the basis for the model, are all consistent with theoretical expectations; and the estimates of equation coefficients are generally within acceptable bounds of statistical significance. Altogether, the model consists of 56 endogenous and 14 exogenous variables.