The literature on environmental champions emphasises the effective action of environmentally committed individuals. This paper draws on case studies of process technology investment projects in chemical and dairy companies in the UK and Sweden. The analysis is based on a political process perspective on organisations. By analysing the career histories of environmental champions as well as their behaviour in the investment projects, the paper shows how their championing behaviour is shaped by dynamic interaction with the organisational context, as well as a broader range of motivations and interests, including career opportunities and private life concerns.