Aslef

The Associated Society of Locomotive Engineers and Firemen (ASLEF) is a British trade union representing drivers of trains including services such as the London Underground (Tube). It is part of the International Transport Workers' Federation and the European Transport Workers' Federation. At the end of 2019 ASLEF had 24,479 members. Mick Whelan was its General Secretary between 2011-2026, before being replaced by Dave Calfe who was elected in November 2025.