The paper analyses how tourism as a sector affects development: not only income and growth, but diversification, human resource development, and infrastructure. It may have lessons for government strategies for a largely private sector industry. It can also indicate how developing countries can integrate their activities into world markets. It shows patterns ranging from direct foreign ownership and JVs through management contracts, joint marketing organisations, and completely national operation. It is responding to technological changes as it depends on communication and transport. An important question for any activity is whether it has particular effects on poverty, through its price, employment, or income effects. An important question is whether, and in what ways, tourism is different from other potential exports for developing countries, that is differences not in the scale or composition of effects, but basic differences in the nature of its effects which should affect how countries appraise it.