The document discusses the history and evolution of ecotourism. It notes that the term emerged in the late 1980s as environmental awareness grew and consumers sought more sustainable tourism options that minimized impacts on the environment. Two broad schools of thought on ecotourism emerged around case studies of its impacts and issues regarding planning and development. The concept continued to develop over subsequent decades as definitions were evaluated and principles like having a natural focus, providing education, contributing to conservation and local communities, and meeting expectations were established.