The volume of cargo handling activities is inextricably linked to ship port schedules, consequently dockwork is subject to fluctuations in demand. To cater for peaks in demand, dockers have grouped together to offer a pool of highly specialised and experienced labourers equipped to provide invaluable assistance to the workforce of the terminal operating companies. The supply of temporary dockwork is regulated in compliance with article 17 of the law of port reform 84/94.