In every manufacturing company there are two types of users who need to work with the output of MRP: the material planner, who is often also the buyer and the production planner/scheduler. The first type of user works with planned purchase orders, the second with planned production orders.

Very few companies have only one user in each of these roles. The business challenge is how to divide the MRP-output between the different people. Material planners, who are often also buyers, and the production planners or production schedulers.