This document summarizes the history of the environmental movement and green building movement. It discusses key events like Rachel Carson's Silent Spring which sparked the modern environmental movement in the 1960s. It also discusses the growth of green building organizations in the 1980s and 1990s and the development of standards like LEED. Finally, it describes the clean tech boom of the 2000s, fueled by concerns over climate change, and why many clean tech startups ultimately failed due to the long timelines required to commercialize new energy technologies.