A 48-hour strike on London's Docklands Light Railway is to go ahead after talks failed to resolve a dispute over claims of a breakdown in industrial relations.
Members of the Rail, Maritime and Transport union will walk out from 5.30am on Thursday and will take other forms of action next week.
The workers, including security staff, cleaners and travel safety officers, are employed by ISS.
RMT general secretary Mick Cash said: "We are supporting our members' action in a bid to force management to honour agreements, pay staff their contractual hours and give their staff proper respect and dignity at work.
"RMT reps have continually chased management to settle the dispute but the company are blatantly ignoring the union's concerns.
"The fact that the company were prepared to kick back in our faces genuine attempts by the union to resolve the dispute in talks over the past week speaks volumes.
"We are expecting further and continuing solid support from our members in this dispute."