Manufacturing process outsourcing (MPO) may surprise many who are familiar with the term, "outsourcing." The concept is quite different. While most would assume outsourcing company functions involve an outside vendor operating in a different location, the intent of MPO is to "run a business within a business." It involves outsourcing manufacturing functions to a vendor who actually operates inside the company's facility, while guaranteeing the quality and cost of output.
Source: Industry Week, http://industryweek.com