Community ecological theory may play an important role in the developm
ent of a science of restoration ecology. Not only will the practice of
restoration benefit from an increased focus on theory, but basic rese
arch in community ecology will also benefit. We pose several major the
matic questions that are relevant to restoration from the perspective
of community ecological theory and, for each, identify specific areas
that are in critical need of further research to advance the science o
f restoration ecology. We ask, what are appropriate restoration endpoi
nts from a community ecology perspective? The problem of measuring res
toration at the community level, particularly given the high amount of
variability inherent in most natural communities, is not easy, and ma
y require a focus on restoration of community function (e.g., trophic
structure) rather than a focus on the restoration of particular specie
s. We ask, what are the benefits and limitations of using species comp
osition or biodiversity measures as endpoints in restoration ecology?
Since reestablishing all native species may rarely be possible, resear
ch is needed on the relationship between species richness and communit
y stability of restored sites and on functional redundancy among speci
es in regional colonist ''pools.'' Efforts targeted at restoring syste
m function must take into account the role of individual species, part
icularly if some species play a disproportionate role in processing ma
terial or are strong interactors. We ask, is restoration of habitat a
sufficient approach to reestablish species and function? Many untested
assumptions concerning the relationship between physical habitat stru
cture and restoration ecology are being made in practical restoration
efforts. We need rigorous testing of these assumptions, particularly t
o determine how generally they apply to different taxa and habitats. W
e ask, to what extent can empirical and theoretical work on community
succession and dispersal contribute to restoration ecology? We disting
uish systems in which succession theory may be broadly applicable from
those in which it is probably not. If community development is highly
predictable, it may be feasible to manipulate natural succession proc
esses to accelerate restoration. We close by stressing that the scienc
e of restoration ecology is so intertwined with basic ecological theor
y that practical restoration efforts should rely heavily on what is kn
own from theoretical and empirical research on how communities develop
and are structured over time.