ASLEF, or the Associated Society of Locomotive Engineers and Firemen, is a trade union in the United Kingdom that represents train drivers and other railway workers. Founded in 1880, it aims to protect the rights and interests of its members, ensuring fair working conditions and safety standards in the railway industry. The union is involved in negotiations with railway companies and the government on issues such as pay, working hours, and job security. ASLEF also provides support and resources for its members, helping them navigate challenges in their professional lives while promoting the importance of the railway sector.