While not denying that tourism has environmental impacts, tourism's potential to aid biodiversity conservation world-wide is great and needs to be harnessed. However, unless precisely explained, the notion of ecotourism clouds the role of tourism in nature conservation. Therefore I define ecotourism as all visits that focus on nature appreciation and the associated infrastructure (park facilities, tours, accommodation, airlines that bring tourists to the area etc.) that supports these visits. This definition, which is used throughout this paper, helps eliminate the false distinction being made between tourism and ecotourism. Tourism, at the international and national political level, has an influential role as a force for biodiversity conservation by being a rationale for placing extra land in conservation reserves, or otherwise by sustainably managing natural areas for their natural values. Using World Heritage Areas (WHA) as an example - perhaps even as an indicator of tourism and its impacts on natural areas the little information available suggests that tourism is not often a threat, but that warfare, clearing for agriculture, and poaching are. Regions with an intact tourism industry are also those more likely to have an intact ecosystem. National parks do act as a catalyst for tourism growth. The question is whether tourism can deliver the financial means to undertake management to neutralize the impacts of tourism on biodiversity, or, perhaps more importantly, to fund more extensive works for biodiversity conservation? Few rigorous economic studies have been carried out to provide answers to this question; to define the link between biodiversity conservation and tourism, and to explore ways of making tourism maintain and expand the resource on which its profits are based, thus making the industry world-wide a major force for conservation.