The World Heritage Convention has been ratified by 158 countries and provid
es an international legal regime for the conservation of sites of global cu
ltural or natural value. There are 33 tropical forest sites listed under th
e convention, mainly for their global biodiversity value. They constitute a
n elite set of biodiversity sites covering approximately 2.5% of the world'
s closed tropical forests and making a significant contribution to the cons
ervation of the world's terrestrial biodiversity. A range of international
initiatives will eventually provide a framework for better conservation and
sustainable management of forests worldwide, but the World Heritage Conven
tion provides an existing mechanism which could quickly be mobilized to saf
eguard the most important forests. In the past sites were selected for list
ing under the convention if they were perceived to have minimal human impac
t. However, ail forests are modified by humans and we contend that modifica
tion need not be inconsistent with the maintenance of global biodiversity v
alues. The convention could have greater impact if it addressed more direct
ly the reality of the ubiquitous human modification of forests. This could
be achieved through use of more adaptive forms of management based on objec
tive criteria and indicators to define tolerance of change and trigger mana
gement responses to achieve desired biodiversity outcomes. We conclude that
an optimal list of world heritage tropical forest sites might include up t
o 100 sites or clusters of sires and that such a network of sites could eff
ectively protect a high proportion of the world's forest biodiversity. The
present rate of attrition of the world's tropical forests suggests the need
for urgent international action to focus on a set of priority sites and th
e World Heritage Conservation could provide the best international framewor
k for such action.