Biologists devised the word biodiversity to allow us to talk about the totality of life on Earth, encompassing everything from the level of DNA and genes, through to individuals, species, and whole ecosystems. Reducing global biodiversity loss in the face of unprecedented population extirpation and species extinction has become a fundamental goal for conservation, and the subject of an array of international, national, and regional policies and goals. The recognition that humans, in some way or other, rely on biodiversity and ecosystems for a great deal has bolstered and driven recent goal setting. The diversity of life we observe not only provides a rich and varied component of the natural world but, ironically, most is hidden in soils and seas and wantonly abused. Together, seen or unseen, they are our natural capital: the engineers and providers of the many benefits which humans accrue from an intact and fully functioning environment. In this chapter, we aim to summarise the developments in international goal setting and measurement for biodiversity and ecosystems; we focus on the past 25 years, when the majority of change has taken place.