- monitors what the Australian intelligence and security agencies do
- conducts inquiries, either self-initiated or at the request of government
- investigates complaints about the agencies
- makes recommendations to government
- provides annual reports to the Parliament.
The IGIS has extensive powers to obtain information and can:
- require any person to answer questions and produce relevant documents
- take sworn evidence
- enter agency premises.
The IGIS' inquiries are conducted in private, but many of them are reported in annual reports.