Climate change and air pollution have major impacts on cancer incidence, treatment, and outcomes. OUCH-I is the only international non-profit organization of cancer health care professionals and advocates focused on mitigating the effects of climate change on cancer care. OUCH-I’s goals are to educate stakeholders (oncology health care professionals, patients, advocates, health systems, professional organizations, policy makers) on the link between climate change and cancer; advocate for sustainable cancer care; and advocate and promote actionable steps in climate mitigation.