This an agreement between an organization and a third-party (mostly an independent specialist professional or a consulting firm) or which moves some of the HR responsibilities and functions off-location, while retaining others. 

For example, an organization  may outsource their  payroll and training while maintaining in-house recruitment or disciplinary processes. Larger sized organizations are more likely to outsource some of their HR functions to a more specialist consulting firm; this is in order for the organization to focus on other aspects of the organization. A common function that is outsourced to specialist professionals, is the advisory side of Human Resources; this is especially when an organization is looking to reduce their members of staff and also shift others. Most organizations usually outsource to places such as Asia, Africa and South America; this is mainly because the cost involved is less expensive.