In this first-ever anthology of Indigenous science fiction Grace Dillon collects some of the finest examples of the craft with contributions by Native American, First Nations, Aboriginal Australian, and New Zealand Maori authors. The collection includes seminal authors such as Gerald Vizenor, historically important contributions often categorized as 'magical realism' by authors like Leslie Marmon Silko and Sherman Alexie, and authors more recognizable to science fiction fans like William Sanders and Stephen Graham Jones. Dillon's engaging introduction situates the pieces in the larger context of science fiction and its conventions. Organized by sub-genre, the book starts with Native slipstream, stories infused with time travel, alternate realities and alternative history like Vizenor's 'Custer on the Slipstream.' Next up are stories about contact with other beings featuring, among others, an excerpt from Gerry William's The Black Ship. Dillon includes stories that highlight Indigenous science like a piece from Archie Weller's Land of the Golden Clouds, asserting that one of the roles of Native science fiction is to disentangle that science from notions of 'primitive' knowledge and myth. The fourth section calls out stories of apocalypse like William Sanders' 'When This World Is All on Fire' and a piece from Zainab Amadahy's The Moons of Palmares. The anthology closes with examples of biskaabiiyang, or 'returning to ourselves,' bringing together stories like Eden Robinson's 'Terminal Avenue' and a piece from Robert Sullivan's Star Waka. An essential book for readers and students of both Native literature and science fiction, Walking the Clouds is an invaluable collection. It brings together not only great examples of Native science fiction from an internationally-known cast of authors, but Dillon's insightful scholarship sheds new light on the traditions of imagining an Indigenous future.