The National Resources Council (NRC) has recently published the results of its analysis of US Environmental Protection Agency (USEPA) research and goals and recommended that it concentrate its energies for microbiological protection of drinking water to Virulence Factor Associated Relationships, or VFAR. In summary, the NRC said that the USEPA should proceed down a pathway similar to that used by the pharmaceutical industry to create new drugs. For several years one process of new drug generation has centered on molecular modeling. This process precludes the often haphazard means of classical drug discovery and can be considerably time and money saving. However, it depends on a detailed knowledge of the underlying pathogenesis of the disease and exact, or very close, information about the structure. Successful implementation of this chemical process also depends on a situation that does not exit in microbiology, that the attachment of the drug to its receptor is static, and not mutable or induced. Unlike chemistry, microbiology is not static but dynamic. Virulence factors may not be naturally present when the microbe is in the environment but only induced after they enter the host, and under very specific microenvironmental circumstances (e.g., pH, salt, heat). These may be unknown, or difficult to reproduce in a laboratory setting. In 1991, Lye and Dufour analyzed a number of commonly accepted extracellular enzyme virulence factors (e.g., protease, lipase, esterases) from naturally occurring HPC drinking water bacteria, and generally found them lacking. Virulence Factor Associated Relationships (VFAR) analysis is an attempt to broaden this strategy (it analyzes for a class of virulence factor rather and each individual in the class, some of which may not be known) and to enhance the discovery of virulence factors within a class. NRC recommends that the USEPA proceed along the VFAR pathway. The USEPA, like all regulatory bodies of its type, actually has two charges: first, the development of health risk assessment parameters by which regulations governing treatment and pathogen removal are generated, and the approval of tests (including the frequency and volume of testing) of drinking water to protect the public health.