Many of the challenging clinical evaluations facing today's practitioner and particularly today's allergist involve suspected hidden environmental exposure, not only to traditional allergens that induce classic symptoms of IgE-mediated disease, but to a wide range of simple chemicals encountered in trace amounts that may be associated with multisystemic symptoms including behavioral and neurologic manifestations. In the litigious social climate in which we live, the increased number of disability and personal injury claims and the ambiguous posturing by the legal profession often dictate a new set of diagnostic rules and norms. These must be considered by allergists and other practitioners in evaluating patients with polysomatic complaints allegedly due to trace environmental contaminants and with little or no identifiable pathology by gross or microscopic examination of tissues or laboratory data. These patients may have been declared totally disabled and may be seeking or receiving large amounts of personal injury compensation. Furthermore, they may be under "treatment" with multiple unproven diagnostic and therapeutic modalities and properly controlled challenge procedures may be necessary to prove or disprove the necessity for these diagnostic tests and therapies. With the ever increasing industrialization of our environment, it is likely that patients with these problems, who present for evaluation, will increase in number. It is therefore prudent for the practitioner to consider sound, comprehensive approaches to diagnoses and management of these conditions and above all to allay morbid fears of clinically relevant disease or immune system dysfunction based on results of isolated laboratory test findings.