The SIA supervises qualified auditors and registered audit firms.
The area of supervision, representing the single largest activity at the agency, covers:
- Inspections: Inspections are performed for qualified auditors and registered audit firms. Both in respect of the special quality control of auditors in public interest entities, and for other qualified auditors.
- Risk-based oversight - enforcement and investigations: Cases are investigated in response to reports or the SIA having opened a case on its own initiative, based on identified and/or suspected risk factors . There is a special decision-making body within the SIA, the Disciplinary Board of Public Accountants, which, among other things, makes decisions in issues relating to disciplinary actions.
- Thematic oversight: This form of supervision is aimed to cover the auditing industry as a whole and against a specific area or audit question.