Hello. I would like to ask can my employer force me to work overtime? I am working Mon - Fri and now he is forcing me to do overtime. There is written in my agreement that my minimum hours of work are 37.5 per week. I signed 48 hour average working week opt agreement, but in my agreement there is written ''You may be requested to work overtime to cover peak trading periods or employee absence. Overtime working is not guaranteed and is optional''. When I do overtime there is only 8 hours break between my shifts. Usually I don't refuse, but this weekend I can't and I already told that. Boss says that I must work and if I won't do so they will change my shift from Friday to Saturday. Can they force me to work? Can they change shift only to me, because I refused. Moreover other employees are not forced to work on Saturdays.