The Accountancy Investigation and Discipline Board (AIDB) was a UK regulatory body responsible for investigating and disciplining accountants and accountancy firms in cases involving serious professional misconduct.

It dealt mainly with:

Public interest cases

Major audit failures

Misconduct by large accounting firms

The AIDB was part of the Financial Reporting Council (FRC) structure and later its functions were taken over by the FRC itself.

In simple terms, the AIDB was a UK body that investigated serious misconduct by accountants and audit firms.