Germany already had auditors before FAVAG. The Verband deutscher Bücherrevisionen (VDB), an association of book auditors that had emerged from a merger of Berlin firms, was constituted in 1900. English and American firms — Price Waterhouse, Whinney's — had opened branch offices in Berlin to serve international business. But there was no unified profession, no licensing regime, no standardized methodology. Several professional associations competed for territory: the VDB itself, the trustees' working group within the German Diplomkaufleute association, the Verband Deutscher Treuhand- und Revisionsgesellschaften, and the Reichsbund Deutscher Treuhand-Aktiengesellschaften. In 1930, the Main Office for publicly appointed auditors was created, requiring that public auditors be formally appointed and audit firms registered. The FAVAG collapse accelerated everything that followed.

The Ordinance of the Reich President on Stock Corporation Law, Bank Supervision and Tax Amnesty was published on September 19, 1931. Among other things, it imposed a duty of disclosure on companies — an annual report, an annual financial statement, and an audit — and set the rules for who could perform that audit. Balance sheet auditors had to be individuals experienced and educated in bookkeeping. Audit firms could only sign audits if one of their owners, board members or managing directors met that bar personally. It was the moment German accounting moved from a craft to a regulated profession. The patchwork of trade associations consolidated. The Institute of Public Auditors in Germany — Institut der Wirtschaftsprüfer in Deutschland, IDW — traces its institutional lineage to this moment.

The IDW is a private association, not a regulator. But it operates the procedural machinery that produces Germany's auditing standards, and German auditors are professionally bound to apply them. The core mechanism is a body of technical committees, each watching its territory: assurance (statutory audits), reporting (financial statements), and advisory (business valuation, restructuring, insolvency). The Hauptfachausschuss — the Main Technical Committee, HFA — sets binding auditing and quality standards. The Fachausschuss für Rechnungslegung — the FAB — does the same for financial reporting. Specialized sub-committees cover banks, insurance, real estate, hospitals, IT systems, the housing industry. Drafts go through a public "Due Process": comments are published, hearings are held, and only then are standards formally adopted. A standard from a specialized committee normally needs the approving acknowledgment of the HFA or FAB before publication. The whole system is designed to make Germany's audits look the same from one firm to the next.

Since the early 2000s, the global trend has been toward the International Standards on Auditing (ISA), produced by the IAASB in New York. The IDW publishes those standards in German translation as ISA-DE, marking the necessary German legal deviations with a special notation — D-Textziffern, or D-text paragraphs — so auditors can see at a glance where the German requirement diverges from the international original. Alongside ISA-DE sit the IDW's own pronouncements: IDW PS (auditing standards), IDW QS (quality control standards), IDW RS (financial reporting statements), IDW S (business valuation, restructuring, insolvency standards), plus a stack of less binding practice notes and Q&As. It is a dense regulatory thicket, but it is the thicket through which every German statutory audit must pass.

The IDW is headquartered in Düsseldorf, with twelve regional Landesgruppen and seven regional offices to cover member interests across Germany. Political work happens out of offices in Berlin and Brussels, where the institute represents the profession to lawmakers and to the European Commission. The IDW is a member of the international IFAC and the European Accountancy Europe, and active practicing members are required to complete an average of 40 hours of continuing professional development per year — the kind of detail that does not make headlines but quietly defines what "audited financial statements" actually means in a German annual report. The work that began as a response to FAVAG in 1929 continues, four offices and ninety-some years later, with no sign of stopping.