Catering workers at a Scottish police college are to walk out on Monday in their campaign for a living wage.
The GMB members are employed by privateer Sodexo at the Tulliallan Scottish Police College in Fife.
Most of them are paid just £6.37 an hour and are pressing for £7.20.
The workers voted unanimously to strike. They banned overtime on February 6 and previously walked out on March 18.
GMB says French-owned Sodexo's chief executive is paid more than 50 times the salary of workers and that Sodexo directors each receive more than £500,000.
Sodexo's profits in Britain rose by three-fifths last year to £43 million.
GMB organiser Richard Leonard said Sodexo's business model was "morally out of joint."
He added: "No-one is worth more than 50 times another worker in any organisation."
A government guided by common sense would respond to news that publicly owned Royal Mail has increased profits to £403 million by scrapping plans to flog off the service.