This paper provides a historical context for this meeting, which aimed to e
xamine critically the way we have defined iron-deficiency anemia as a publi
c health problem. The terms and concepts used to define the problem are rev
iewed first, followed by estimates of the global prevalence of the problem
from 1985 to 2000. It is argued that recent estimates are not credible and
that we must redefine the problem in terms that are important, measurable a
nd addressable. This meeting was designed to take first steps toward that g
oal, namely, to identify the causal factors (e.g,, iron deficiency vs. iron
-deficiency anemia vs. severe anemia from any cause) that link iron-deficie
ncy anemia to important health outcomes and to estimate the magnitude of th
eir effects in public health terms.