EcoBuddhism represents a modern American attempt to articulate an authentically Buddhist response to present environmental problems. This article isolates the basic features of the movement and notes a substantial shift away from traditional Buddhist cosmology. Most notably, ecoBuddhism constructs a picture of the world that is intrinsically teleologic. The factors that have given rise to this reworking of tradition are analysed and the question of authenticity is tested against a variety of critical methodologies. The ‘protestant Buddhism’ thesis, in particular, is examined and found wanting. The conclusion drawn is that ecoBuddhism should be classed as a form of reflexive apologetics generated primarily by forces originating from within the Buddhist tradition itself.