This paper advocates the use of what we term a CC (command control) method for explaining the behavior of economic systems in the transition from command to market economies. The specific implementation involves controlling Polish money balances for the effects of price deformation or shortage in the central planning period up to 1989, and asking whether the error-correction process for shortage-adjusted money balances is stable after the price liberalization and currency convertibility measures of January 1, 1990. We find no evidence of a structural break from 1990, suggesting that the CC method provides a basis for drawing at least tentative inferences about behavior under the new regime
