This is a series of checkpoints that are required by the Contract to determine the partial completion or substantial completion of the major work at intermittent time during the contract period . It lays out the extent of works required to be completed at a certain time interval ( with a key date ) after commencement of work in order to govern the programme and progress of the project .

In case there is any variation work instructed by the Engineer that interrupts the works progress of the critical activities to achieve these milestones , an application for extension of time ( EOT ) may be required ; or the Engineer should issue instruction to accelerate the affected works should he still wish to maintain the milestone works at the specified key date ( KD ).