Rail operator East Midlands Trains - which operates trains between Sheffield and London, Nottingham and Manchester - is going green.
It is holding a programme of events over the coming week to raise awareness of environmental issues and simple steps employers and passengers can take to reduce environmental impact, such as recycling.
Activities will take place at stations managed by the firm.
On Thursday, a joint event with Stagecoach Supertram at Sheffield Station will include a display of environmentally-themed posters produced by patients at Sheffield Children’s Hospital.
David Horne, EMT managing director, said: “Green Week is an established and important part of our efforts to protect the environment and become a more sustainable business.”