This paper explores the ways in which libertarian natural rights theories have confronted the environmental challenges brought about by property acquisition. It has three aims: first, to challenge some supposed libertarians on the issues of nature and technology; second, to explore the environmental potential of the Locke/Nozick stipulation; third, to point out some of the difficulties to which the stipulation leads when it is applied to solving environmental problems. We claim that the stipulation leads to two outcomes, depending on how it is interpreted. The first provides the possibility of effectively developing a strong environmental libertarianism, but only at the cost of imposing severe restrictions on acquisitions; the second avoids these restrictions, but at the cost of renouncing to any meaningful environmental policy. The paper concludes with some reflections on the relation between the theory of property and environmentalism.