In a manufacturing environment “Internal Customers” are the people, machines, or processes being supplied with the products or parts made in preceding work area(s).
Comments: Although both areas (the supplying and receiving areas) work for the same company, it is a good practice for everyone and every department to treat those they supply to as if they were prized customers. This attention to curtesy, delivery performance, and special needs within the Internal Customer area will yield a positive interaction, improve communications, and increase throughput.
Very often we find Internal Supplier areas not communicating with Internal Customers areas or perhaps, even worse competing with each other. Building the “Customer/Supplier” relationship is part of changing to a “Lean Culture” as an organization.