I agree with everyone that says that the project manager should discuss with each member throughout the duration of the project. In the beginning, Project managers should already have schedules of all members. If there is an emergency, I would suggest hold a meeting with the member. Ask them who could replace he or she for the emergency and ask for the work that he or she been working so the project knows what the department is currently working on and if the project manager can give a hand. There should be constant friendly communication between the members and project manger because the project is very important and if know one speaks up then the project and company is hurt due to obstacle delays. If the member is working with another group, it is job to inform the project manger and another from the group so he or she can be able to multitask between two groups.