A concept within the UK Agency Workers Regulations (See “Agency Workers Regulations”) that provides for a number of circumstances in which breaks in the assignment of a temporary agency worker do not prevent them from completing the 12-week qualifying period upon which they benefit from parity in basic employment and working conditions with equivalent permanent workers. These provisions can best be explained by thinking of the qualifying period as a clock that runs from 0 to 12. Sometimes a gap between assignments – or a move to a new assignment – will mean that the clock is reset to 0 and must start again. In other circumstances a break will merely ‘pause’ the clock, which will then continue to tick when the agency worker returns. In some limited circumstances, the clock will continue to tick even if the agency worker is not working on an assignment.