"Call-On" at the Docks was the notorious process used for hiring casual labour to unload ships.

 From the early days, the dock companies employed very few permanent workers. The vast majority were casual workers hired to unload ships as they arrived at the docks. Much of the work was seasonal, in some months fewer ships came in, at other times many more were waiting to discharge their cargoes. These workers were "called-on" for perhaps  only a few hours or for a few days, as and when labour was needed. Masses of men would gather at dock entrances and when the calling foreman appeared there would be a mad scramble to catch his attention to try and get a "ticket" to work. "Call-on" happened twice a day and in the frenzy to get a ticket men got injured or were even trampled to death. Hours or days were spent in all weathers standing waiting in the hope of getting work. No work meant no money to take home, which meant hunger, or eviction for not paying the rent,  was never very far away. Work was heavy and back-breaking and, being out in all conditions such freezing or wet weather, was often dangerous. Anyone seen to be slacking or who infringed some minor regulation was liable to instant dismissal, reducing still further the likelihood of other work, either inside or outside the dock. Sometimes men organised themselves into work gangs, they worked well together and brought a degree of safety to their dangerous environment. The gang system was unpopular and open to abuse.

Dockers only became full time employees as late as 1967.