He joined the Amalgamated Society of Woodworkers, which subsequently became part of the Union of Construction, Allied Trades and Technicians (UCATT).
In 1971, he was prominent in the Upper Clyde Shipbuilders work-in, which attempted to save the shipyards.
[3] As general secretary, Ritchie led the group of trade unionists working on the 2012 Olympic Games construction project, and campaigned against nominal self-employment of building workers and for improved safety on construction sites.
[2] He was re-elected in 2009, again beating Dooley, but it later emerged that almost half the union's members were never sent ballot papers, and the result was declared void.
Ritchie declared his intention to stand in the re-run election, but before it took place, he was suspended over unconnected allegations of expenses fraud.