This chapter examines the implications of financialisation for environmental sustainability. It shows that while financial investment has long resulted in economic changes that affect nature, this relationship has seen important changes in recent decades as the process of financialisation has unfolded. In particular, we show that financialisation has encouraged the rise of new kinds of financial instruments that are tied to natural resources and environmental change. These new financial instruments have relied on an abstraction of nature from its material form, and have transformed elements of the natural world into purely financial assets. These kinds of new financial tools are often based on indexes or pooled funds that track the performance of real things such as natural resources, land, carbon, or the weather. For investors, these instruments are purely financial vehicles. But the fact that nature ultimately forms the underlying base for this financial investment means that this financial activity can, and often does, have real world consequences. These effects, however, are often distanced from their financial origins, and are not always accounted for in sustainability policy and governance.