Finance Act 2000 (extract covering the application of IR35) Schedule 12 to this Act has effect with respect to the provision of services through an intermediary. SCHEDULE 12 PROVISION OF SERVICES THROUGH AN INTERMEDIARY Engagements to which this Schedule applies 1. - (1) This Schedule applies where- (a) an individual ("the worker") personally performs, or is under an obligation personally to perform, services for the purposes of a business carried on by another person ("the client"), (b) the services are provided not under a contract directly between the client and the worker but under arrangements involving a third party ("the intermediary"), and (c) the circumstances are such that, if the services were provided under a contract directly between the client and the worker, the worker would be regarded for income tax purposes as an employee of the client. (2) In subparagraph (1)(a) "business" includes any activity carried on- (a) by a government or public or local authority (in the United Kingdom or elsewhere), or (b) by a body corporate, unincorporated body or partnership. (3) The reference in subparagraph (1)(b) to a "third party" includes a partnership or unincorporated body of which the worker is a member. (4) The circumstances referred to in subparagraph (1)(c) include the terms on which the services are provided, having regard to the terms of the contracts forming part of the arrangements under which the services are provided. (5) The fact that the worker holds an office with the client does not affect the application of this Schedule. This is the introduction describing the application of IR35. The full text of the Act, defining the intermediary, and detailing how to account for 'relevant engagements' can be found here.