ERM (Environmental Resources Management) is the world's largest pure-play sustainability consultancy, providing environmental, health, safety, risk and sustainability advisory services. Headquartered in London, ERM employs around 8,000 people across more than 150 offices in over 40 countries. The firm traces its roots to 1971 and is majority-owned by KKR, which acquired its stake in 2021 at a valuation of roughly $2.7-3 billion.