Malaysia features some of the most spectacular national parks in the world. Often hotspots of biodiversity, these parks have become a major attraction for tourists. Although a source of revenue, such tourism presents a threat to the environmental integrity of conservation areas. This study analyses ecotourism in Malaysian national parks from different angles by asking different groups of tourists (both foreign and domestic) and experts about their opinions, experiences and needs. The needs of foreign individual and group travellers were analysed with a questionnaire in Gunung Mulu National Park. Experts of conservation and tourism, including park managers and tour operators, were asked to assess the state and potential of ecotourism in Malaysian national parks. Results show that the increasing heterogeneity and number of visitors and their different needs can put a strain on the environmental integrity of conservation areas. This study makes recommendations to mitigate such strains and to further sustainable tourism. Index.