Group 821 - Office administrative and support activities of International Standard Industrial Classifications of All Economic Activities (ISIC) Rev.4 includes the provision of a range of day-to-day office administrative services, such as financial planning, billing and record keeping, personnel and physical distribution and logistics for others on a contract or fee basis.

This group includes also support activities for others on a contract or fee basis, that are ongoing routine business support functions that businesses and organizations traditionally do for themselves.

Units classified in this group do not provide operating staff to carry out the complete operations of a business. Units engaged in one particular aspect of these activities are classified according to that particular activity.