The Bukit Barisan Selatan National Park in southern Sumatra (Indonesia) has been on the UNESCO list of World Heritage Sites since 2004. Home to tigers, elephants, and rare Sumatran rhinos, the Park is also home to numerous squatters since the early 1970s. Part of the Park was restored after forcible evictions in the 1980s. However, since the end of General Suharto's authoritarian rule in 1998, the number of squatters has been on the increase. This paper provides for the first time a reliable estimation of the number of people encroaching in the Park and presents a profile of the various kinds of squatters living in and around the Park. It shows that all encroachments are not alike, nor are the squatters. Poor landless migrants side with opportunists taking advantage of weak law enforcement, while local politicians try to build a constituency by backing illegal activities in the Park. As a consequence, any action to salvage the Park will have to take into account the complexity of the political ecology, policy environment, and socio-economic nature of each encroachment.