Anna-Lena Thomsen

Anna-Lena Thomsen is a Senior Manager at Grant Thornton and is next to engagement work  responsible for quality assurance and the assurance methodology of sustainability information in the One ESG team. Her focus has been on auditing sustainability reports and disclosures in accordance with Art. 8 of the EU Taxonomy Regulation. Furthermore, she supports clients across all industries in preparing for future reporting in accordance with the CSRD. She has many years of experience in auditing annual and consolidated financial statements, particularly of subsidiaries of international parent companies. In addition, she has 2.5 years of experience in technical policy work at the Institut der Wirtschaftsprüfer in Deutschland e.V. (IDW) in the areas of standard setting and implementation. She is an author and speaker on auditing and assurance topics.

Fields of expertise

• Assurance on sustainability reports or individual KPIs and transition plans in accordance with ISAE 3000 and ISSA 5000 with limited and reasonable assurance
• National and international auditing standards incl. fundamental issues in the area of sustainability assurance methodology
• Audit of (group) financial statements HGB/IFRS

Memberships

• IDW working group on the assurance of sustainability reporting
• IDW working groups CSRD/ESRS as well as climate claims in accordance with EmpCo

Publications

• WPg 01/2026, p.14, Zum Audit Readiness Check von Nachhaltigkeitsberichten: Mehrwert für Ersteller und Prüfer [For the audit readiness check of sustainability reports: Added value for preparers and auditors]
• WPg 01/2023, p.3, Neue IDW Prüfungsstandards für die Prüfung von Abschlüssen und Lageberichten weniger komplexer Einheiten (IDW PS KMU) [New IDW Auditing Standards for Auditing the Financial Statements and Management Reports of Less Complex Entities (IDW AuS SME)]
• Author of KMU Prüfungspraxis – Spezieller Leitfaden für die Prüfung weniger komplexer Einheiten [SME Audit Practice – Special Guidelines for Auditing Less Complex Entities]