over which measurements are made or averaged, statistical form of the standard used to determine the allowable number of exceedences, and the effective and efficient implementation of emission-control programs to achieve the NAAQS.
In the future, it will also be important to ask whether the PM research and this committee's role offer a model for conducting other major scientific investigations. Equally challenging and contentious scientific inquiries are under way for such issues as endocrine-disruption effects of chemicals and potential health impacts of genetically engineered organisms. Are there aspects of the way in which the PM research program is being planned, conducted, and overseen from which these other efforts could usefully draw? Among the key elements of the PM research example that might prove useful in other arenas are the development of a multidisciplinary research portfolio designed to address key public-policy questions, the laying out of a multiyear commitment to implementing the portfolio, the establishment of management mechanisms to ensure interagency and public-private coordination, the construction and continued use of a research-inventory database, and the continuing oversight and evaluation of the program by an outside, multidisciplinary committee. Of course, the evaluation of the success of the PM example will require others, outside this committee, to make fresh judgments as to which elements succeeded and which did not. However, some elements that succeeded might not be applicable to every other field of science. It is appropriate to begin documenting and evaluating key elements of the PM research example soon so that future observers can measure and learn from its success.