Due to come into force in October 2011 the Agency Workers Regulations aim to ensure "“the basic working and employment conditions of temporary agency workers shall be, for the duration of their assignment at a user undertaking, at least those that would apply if they had been recruited directly by that undertaking to occupy the same job”.
There had been some specualtion that although contractors working through Umbrella Companies were initially going to be caught by the new regulations the new Tory Government would review this and make them outside their scope (as contractors working through their own limited companies are outside the scope).