The Definition of Outsourcing

Outsourcing has been defined as:
"A contractual relationship where an external organisation takes responsibility for performing all or part of an agency's Information Technology functions. This can involve a partial or complete transfer of staff and/or resources."
& also as
"An arrangement whereby a third party provider assumes responsibility for performing information systems functions at a pre-determined price and according to predetermined performance criteria."
- Australian Computer Society paper on outsourcing

"Work done for a company by people other than the company's full-time employees".
- InvestorWords

"Outsourcing is when a company purchases a product or process from an outside supplier rather than producing in house. This is different from subcontracting because the customer does not own the raw material or manufacturing process but buys the product based on the specifications offered by the supplier. The customer trains and develops the supplier to form a supply chain partnership."
- Outsource Solutions, LLC

"Outsourcing is an arrangement in which one company provides services for another company that could also be or usually have been provided in-house. Outsourcing is a trend that is becoming more common in information technology and other industries for services that have usually been regarded as intrinsic to managing a business. In some cases, the entire information management of a company is outsourced, including planning and business analysis as well as the installation, management, and servicing of the network and workstations. Outsourcing can range from the large contract in which a company like IBM manages IT services for a company like Xerox to the practice of hiring contractors and temporary office workers on an individual basis."
- SearchSAP @ SearchTechTarget.com