Across the political sprectrum, it is frequently assumed that environmental problems can adequately be described as challenges to all humans (and perhaps all other species).  Yet short of truly global environmental calamities--such as perhaps a global thermonuclear war with subsequent nuclear winter--most environmental issues affect different groups within society quite differently.  Moreover, which phenomena given groups of people define as environmental problems depends substantially on the specific social positions those groups occupy.  This paper argues for these claims both theoretically and empirically, using historical illustrations from two very different countries--the United States and Thailand.  Demonstrating the applicability of such claims in both developed and developing country contexts suggests that if notions of sustainability are to be analytically useful in global discussions of environmental problems they will have to contain positions regarding the question "Sustainability of what and for whom?"  Furthermore, these positions will necessarily involve taking stands in traditional political struggles structured around axes such as class, race, and gender.  It is in terms of the positions they take in such traditional political struggles that the precise meaning of any given group's environmental politics and politics of sustainability will be defined.