The Last Planner System is based on a traditional planning
system, and is performed by field foremen; the condition of
(SHOULD-CAN-WILL-DID) is implemented. Figs. 8.1 and
8.2 represented the diagram of the Last Planner System.
A reliable assignment, one that gets done at the required
time, determines what WILL be done, after considering both
what SHOULD from higher-level schedules and what CAN
be done based on the situation at hand. Assignments are likely
to get done when they are well defined, resource sound, in the
right sequence, and within the capacity of the crew. The last
planner’s job is to make certain task in the assignment that
meets these criteria and to reject assignments that do not. Last
planners can reasonably commit to completing the tasks on
weekly work plans that meet these criteria. To be effective,
production management systems must tell what should be
done, what can be done, and what will be done; then, they
compare what was done to improve planning [15]. The term
SHOULD is considered as: Hopefully; CAN means: Probably;
and WILL means: Absolutely. Fig. 9 illustrates the possible
relationships among SHOULD, CAN, and WILL.