In 1999, a scientific committee assembled under the auspices of the National Research Council issued a critique of RAND's 1994 Controlling Cocaine report. The committee concluded, [T]he findings of the RAND study do not constitute a persuasive basis for the formation of cocaine control policy. In the current document, RAND's Drug Policy Research Center rebuts the committee's claim. The Center shows that most of the committee's criticisms rest on an incomplete understanding of the model used in the RAND report or do not result in important changes in the findings based on the model. The two remaining criticisms are that the data on cocaine treatment effectiveness are not adequate to support modeling and that the mode of price transmission down the cocaine production pipeline may be different from that assumed. The Center acknowledges these points as potentially valid but holds that models need not have negligible probability of error to be useful as decision aids.