Birds are a major feature of many ecotourism marketing materials. Bird logos, bird photographs, bird diversity, bird-viewing opportunities and bird checklists are commonplace in ecotour brochures, websites and trip or lodge documents. Birdwatching is a large and growing specialist sector of the ecotourism industry (Jones and Buckley, 2000), and provides much of the customer base for manufacturers of high-end binoculars. All forms and aspects of ecotourism have some impacts on birds, both resident and migratory species, but these impacts differ enormously in size, scale and significance. In many cases the impacts of ecotourism on birds may not be apparent to the ecotourists, or tour operators themselves. There are also examples, however, where impacts on spectacular bird populations have reduced the attractiveness of entire tourist destinations. Perhaps best known of these are the flamingoes of the Camargue, France (Feltwell, 1996). This chapter reviews published scientific literature on such impacts in an attempt to identify any general patterns and to illustrate the degree of variation. It draws on two previous reviews (Hockin et al., 1992; Liddle, 1997) as well as more recent and additional literature. In particular, it relies on these authors for citations to studies published in European languages other than English.