We have several Eastern European staff - for them they have Worker Registration Cards and Certificates but only valid if working for us (if they want to move companies they have to re-apply) These are issued by Home Office and apply to those states that have applied or on waiting list to join EU i.e Lithuania/Latvia.The Home Office are very helpful in advising you of who can/can not work although regulations have been tightened recently especially for what they term (I wouldnt) non-skilled positions.