A high priority has been placed in Iran in recent years on developing non-oil sources of income and tourism has been identified as one important area of the economy for development. The development of niche types of tourism such as ecotourism or cultural tourism – both the subject of this paper -is clearly in line with the public policy objective of developing non-oil sources of income. Environmental protection is an obligation on the government under Principle 50 of the Constitution of the Islamic Republic. It is therefore appropriate to consider what role the country’s vast cultural heritage resource can play in ensuring more environmentally sustainable forms of tourism development. Since even ecotourism developments can have negative environmental consequences by development of other forms of low intensity tourism (including cultural tourism) must be an important element in Iran’s policy agenda in this area. The promotion of cultural tourism in Iran should aim therefore to build on the positive impacts while minimising the negative ones. Policies for development of cultural tourism should also take into account the principles and objectives of sustainable development which are set out here within the context of tourism projects. A further reason to look at the role of cultural heritage in this respect is its intricate relationship with the natural environment, as evidenced by the 1972 Convention on the Protection of the World Cultural and Natural Environment of UNESCO. It should be remembered that heritage is a very broad concept that encompasses within its scope landscapes, archaeological sites and built environments as well as cultural practices and knowledge. All of these are relevant to the sustainable development and management of tourism. It also has a potential for contributing to sustainability in itself. This article will therefore consider the cultural heritage – as a tourism resource base - from all of these dimensions.