Unsustainable patterns of human occupation have detrimentally affected the natural world, disrupted ecosystems, and placed the long-term health of humanity at risk, making environmental sustainability a topic of paramount importance to occupational therapists. To minimize damage to the natural environment and promote human health, well-being, and justice, occupational therapists should develop knowledge of environmental sustainability and human occupations. This chapter aims to provide readers with a basic understanding of the impact that human occupation has on the environment, the effects of climate change on human occupation, and the ethical dimensions of sustainability. Additionally, this chapter will introduce readers to the application of occupational therapy theory to environmental sustainability concepts, as well as initiate a discussion of environmental sustainability in occupational therapy practice settings, treatment, and education.