Introduction The overlapping of construction activities is a project management technique which helps a project to be completed as quickly possible. However, it inherently leads to increased risk and can jeopardise the insurance in place. This is even more true when two separate design and construction projects overlap forcibly and are knowingly implemented concurrently in the same area. In a recent case, the Greek courts found that the multiple damages which one constructor had caused to another's works were not sudden and unforeseen and did not qualify as one event. Facts A company belonging to a railway group specialised in implementing rail infrastructure works awarded the plaintiff the project of constructing an underground fibre optic grid running along both sides of a railway track. A few months later, another contractor (Contractor 2) was awarded the project of upgrading the railway track along a 22km section of the network, where and while the plaintiff was working. The second project, although awarded by another entity, also had to be implemented by the first awarding company, which now had to supervise two independent but overlapping construction projects. Following several meetings between the supervising entity and the plaintiff, the latter was required to submit detailed additional information regarding his progress, including updated Gantt charts, monthly schedule reports showing all deviations from the agreed baseline schedule and weekly reports on the work performed each day and the work to be performed on each day of the following week.