This paper is intended to assist development professionals in assessing the scale and relevance of tourism to economic development in developing countries. How should national and international data on tourism be interpreted from a development perspective? What are the caveats and myths that need to be taken into account, and what further information is needed? There is a wealth of data on tourism, but little is accessible to non-tourism specialists, and most focuses on growth trends in the industry, rather than its contribution to development in poor countries.