Doing Environmental Ethics explains how we may transform our fossil-fuel-burning economy, which continues to intensify our ecological crisis, into a circular and ecological economy. The text resists political corruption and personal greed by gleaning ethical insights from our philosophical and religious cultures and by embracing the scientific Gaia hypothesis for the Earth. Its reasoning ascribes intrinsic worth to uplifting duties and rights as well as inspiring virtues and relationships, and tests applying these values by predicting the likely consequences of acting on them. It affirms all life has value for itself, and that human life also values reasoning and feelings and being ethical.

The third edition examines US and international environmental policies through 2018. It analyzes the Trump administration's repudiation of the environmental policies of the Obama administration and its new rules slashing the social costs of climate change. The text reviews a draft UN treaty that would impose human rights and environmental constraints on transnational corporations, but it also highlights outstanding examples of corporate upcycling and low-carbon innovation. Finally, the third edition explains why food security requires protecting the food sovereignty of farming communities and cooperatives, as well as public policies ensuring fair profits for farmers practicing agro-ecology.