Published to accompany the first UK retrospective of Olafur Eliasson's work, this book is conceived as an illustrated `field guide' to his practice. Featuring a substantial conversation between the artist and the Tate curator Mark Godfrey, as well as a range of short dialogues with a strikingly varied range of people working both inside and outside the arts - from anthropology, economics, political science, and biology to architecture and urbanism, dance, music, and food - the book provides readers with a `compass' to Eliasson's thinking: a 360-degree view of the frames of reference that inform his work. Eliasson builds such conversations into his daily life and work. They help him not only to understand other people's unique fields of knowledge, but also to ask, `What does my understanding of your knowledge do to my understanding of the world?', and touch on topics as wide-ranging as the social and cultural factors that contribute to social trust, the `topography' of scent, the chronobiological effects of light, public space and civic infrastructure, and the power of art. The interweaving of these texts with stunning photography of his remarkable and immersive works provides an insight into what Eliasson calls his ongoing aim of `reaching out into the world'.