There is substantial scientific and public concern about the potential
effects of occupational and environmental toxicants on reproductive h
ealth. These effects include impaired functioning of the reproductive
systems of men and women as well as a broad spectrum of developmental
problems expressed in offspring. Research on reproduction and developm
ent is among the most complex undertakings in biomedical research. Thi
s complexity is due in part to the intricate biology of reproduction,
the multiple targets involved (male, female, and offspring), the uncer
tainties in extrapolating from animal models to humans, and the proble
ms involved in accurately characterizing exposures and outcomes in epi
demiologic investigations. However, given the relatively brief history
of research into toxicant-induced reproductive health effects, we hav
e made enormous strides in our knowledge over the past decade. In part
icular, recent advances in reproductive biology and biotechnology and
in the development of biological markers of exposure, effect, and susc
eptibility are greatly enhancing our ability to study cause-effect rel
ationships. In this paper, the Research Needs Working Group proposes w
ays to apply existing knowledge to better protect reproductive health
and suggests directions for future research. Fulfilling this challengi
ng agenda will require responsible cooperation by labor, industry, gov
ernment, individual citizens, and the scientific community. Further re
search and collaboration are essential to both prevent adverse reprodu
ctive and developmental outcomes and to formulate a sound scientific b
asis for policy making.