Two methodological steps in the study of peoples' concerns are elicita
tion and classification. Elicitation of concerns through analytical me
thods such as surveys can be supplemented with techniques that perform
more diversively. We present two examples of how this can be accompli
shed: one in the expert community and one in the lay community. A clas
sification taxonomy is a subjective choice of the researcher and it ca
n only be evaluated against the stated objectives of the research. We
present a classification schema that is explicity oriented toward diag
nosing the substantive needs of public discourses about risk decision
making. To illustrate how concerns can be elicited in a social setting
and how this classification tool can be applied, we report on a publi
c participation exercise in New Jersey where citizens discussed the im
pacts of land application of sewage sludge at an experimental farm.