After a career in schools, I joined the University of Manchester as an academic in 1984 teaching and researching mathematics education. My main interests for many years were in applications and projects involved in learning and teaching mathematics, especially as regards access and equality, which led me to situated cognition and CHAT. Without leaving these aside, now I am leading a newish research group called the Green Research in Education Group (GRiEG) and hoping to reach out across the disciplines and internationally to build alliances to meet green global challenges to sustainability. I am also a member of MCA/CP editorial collective. Publications: https://www.research.manchester.ac.uk/portal/en/researchers/julian-williams(43a8faeb-b800-45b6-9693-ba7d801d4f40)/publications.html  or ORCID 0000-0003-0161-0532