The history of climate change and the history of architecture are connected in many ways: while architects contributed to building the fossil-fuel-driven world that has led to the current ecological collapse, they also explored and developed various alternatives to mitigate the effects of global warming. Using time as a conceptual lens, this book bridges the past, present, and future in new ways, leading to an architecture of climate change. It's About Time presents historical and contemporary projects - from solar houses to autonomous structures and from earth buildings to green Utopias - along with over 45 key moments in the history of environmental awareness. Applying transition research, the book conceptualizes the present as the moment in which awareness, urgency, and opportunity converge to point toward radically sustainable futures. It shows how the architect can integrate time into committed design practices at three distinct velocities: that of the activist, the accelerator, and the ancestor. Serving as both a handbook and a source of inspiration for designers, It's About Time is intended for architects, educators, students, civic agents, and everyone involved in shaping the plural futures of our contemporary landscape. Urgent in its message, it asserts that the momentum to realize change has arrived, and that the field of architecture plays an important role in the systemic transitions we are moving toward.