Olympic security staff must ensure venues are safe and prevent demonstrators from bringing equipment like banners and tents into the stadiums and arenas.
At the same time they must ensure that their work does not create long queues leaving spectators unable to see the events they have tickets for.
All of this will be achieved says G4S, the company that is in charge of the recruitment drive.
But some staff who have worked on the operation have told ITV News they have witnessed security breaches by G4S staff already working at Olympic venues.
More top news
Medical charity worker relates how he and colleagues tried to save patients and staff following devastating air strike.
Union leaders and officials from a range of campaign groups will address demonstrators as Conservative party conference gets under way.
Teachers union says workload, pay and low morale drive educators away from the profession.