The theory of constraints is a method used to continuously improve manufacturing and non manufacturing activities. It is characterized as a "thinking process" that begins by recognizing that all resources are finite. Some resources, however, are more critical than other. The most critical limiting factor, called a constraint, become the focus of attention. By managing this constraint, performance can be improved. To manage the constraint, it must be identified and exploited (i.e.,performance must be maximized subject to the constraint). All other actions are subordinate to the exploitation decision. Finally, to improve performance, the constraint must be elevated. The process is repeated until the constraint is eliminated (i.e., it is no longer the critical performance limiting factor). The process then begins anew with the resource that has now become the critical limiting factor. Using this method, lead times and, thus, inventories can be reduced.