About us

Dr. Peter Happe Steuerberater
Dr. rer. pol. Peter H. Happe
Fachberater für internationales Steuerrecht
Certified Public Accountant - C.P.A. (State of New York)

GHM GmbH Steuerberatungsgesellschaft is legal successor to Dr. Peter Happe Steuerberatung, Cologne, and was founded by Dr. Peter Happe. GHM GmbH Steuerberatungsgesellschaft is the German-based communicating tax firm of GHM Partners AG, Zug, a Swiss firm of tax advisors likewise co-founded by Dr. Peter Happe. Together, these two firms do business under the name of GHM Partners.

In 2014, GHM Partners (GHM Partners AG and Happe Steuerberatung) were designated for Top tax firm for international tax law by the weekly German magazine FOCUS (FOCUS special issue: “Erben und Vererben / Legacies and Inheritance”, February/March 2014, p. 106).

Under the name GHM Partners, a total of 14 professionals (tax advisors, Swiss tax experts, trustees, lawyers and notaries), and a back-office of 10 specially qualified members of staff who work in Germany (GHM GmbH Steuerberatungsgesellschaft) and in Switzerland (GHM Partners AG), cooperate across bordersin the area of international law and international tax law.

Dr. Peter Happe studied for a “Diplom-Kaufmann” degree in business administration at the University of Münster (top 5% of his class), subsequently acquiring his doctorate (Dr. rer. pol., summa cum laude) at the University’s Institute of Auditing under the supervision of Prof. Dr. Dr. h.c. Jörg Baetge. In 1998, Dr. Happe was granted the occupational title ‘Steuerberater’, entitling him to provide advice on German taxes in a professional capacity.

Dr. Happe attended classes in taxation and business law at a university in New York City, where he also worked as a tax advisor and CPA assistant. In 2000, Peter Happe was appointed Certified Public Accountant by the State of New York.

Before becoming self-employed, Dr. Peter Happe worked for many years with the international law firm Clifford Chance and was a tax partner of the law firm Dewey Ballantine. He was also Chief Financial Officer and member of the board of a private equity fund management Company with almost 1 bn. assets under management in Zurich, Switzerland.

Dr. Peter Happe focuses on German and international corporate and partnership taxation. He also has extensive experience in advising high net-worth private individuals, health care professionals, hospitals and institutions, as well as charitable organisations and domestic and foreign trusts.

Having spent long periods living abroad and working in an international environment, Peter Happe’s main focus is now on international taxation.

In view of his sound knowledge and long-standing experience in this area, Peter Happe was appointed ‘Specialist Consultant for International Tax’ by the Chamber of Tax Advisors in May 2010.

After qualifying in 2011, Peter Happe was also appointed "Specialist Consultant for Corporate Succession " by the German Tax Advisor Association (Deutscher Steuerberaterverband e.V. - DStV) in 2011.

He also was appointed "Specialist Consultant for the Healthcare Sector" by the German Tax Advisor Association (Deutscher Steuerberaterverband e.V. - DStV) in 2017.

Dr. Peter Happe has worked as a lecturer at the Federal Fiscal Academy, the Zeppelin University Friedrichshaven and at the University of Dresden, and he has published numerous articles on tax law and tax accounting as well as accounting under IFRS and US-GAAP.

Dr. Peter Happe is also on the advisory board of a brand manufacturer, and a member of the board of trustees of the non-profit foundation “Stiftung Bürgermut”, Berlin, www.buergermut.de. The founder and the chairman of the board of trustees is the businessman and former MP and Berlin Senator Elmar Pieroth. The former German President Richard von Weizsäcker was a partner of “Stiftung Bürgermut”.

Dr. Johannes Mittermaier, LL.M.
Dr. Johannes Mittermaier, LL.M.
Attorney-at-Law (New York)
Certified Public Accountant (New York)

Education / Career
  • Study of Law and Economics at Universität Bayreuth (Dr. rer. pol.) and New York (LL.M. - New York University; Certificate of Advanced Graduate Study in Public Accounting – Pace University Lubin School of Business)
  • Over 20 years of practice in international tax and legal consulting in the U.S. and Germany, thereof twelve years with KPMG in New York and Frankfurt including Head of U.S. Desk Tax

  • U.S. tax and German international tax law; including treaty law and transfer pricing
  • Tax planning for and restructuring of U.S. inbound and outbound investments; including mergers and acquisitions
  • U.S. estate planning and administration including trusts
  • Chapter on partnership taxation in the U.S. in Personengesellschaften im Internationalen Steuerrecht [International Partnership Taxation]; Editors Wassermeyer/Richter/Schnittker, Verlag Dr. Otto Schmidt, Cologne, 2010 und 2nd Ed. 2015
  • Chapters on taxation of individuals and taxation of partnerships in German Tax Guide; Editor Amann, Kluwer Law International, The Hague, 2001
  • Personengesellschaften im Verhältnis USA-Deutschland, [Partnerships in the U.S.-German Setting], Physica-Verlag, Heidelberg 1999

Other / Memberships
  • AICPA – American Institute of Certified Public Accountants
  • IFA – International Fiscal Association
  • IBA – International Bar Association
  • Association of the Bar of the City of New York.
  • Deutscher Verein New York

Guénolée Riboulet Wirtschaftsprüferin
Guénolée Riboulet
German Chartered Accountant

Guénolée Riboulet has broad experience doing buy-side due diligence, supervising closing audits and managing vendor assistance projects – both for strategic and private equity investors, as well as for businesses and consortiums of all sizes. An expert in her field, Guénolée Riboulet also has the required skills for auditing annual financial statements in an international context.

We are pleased to offer you this service in close collaboration with CAFRAL GmbH Wirtschaftsprüfungsgesellschaft, an audit firm with which we have a cooperation partnership.

Before working for GHM and founding CAFRAL, Guénolée Riboulet spent eight years at KPMG and was employed by MAZARS for nine years. Most recently, she ran her own accountancy practice where she focussed mainly on performing annual audits and providing transaction services.

Guénolée Riboulet is bilingual in German and French and also speaks fluent English.

Other colleagues who work in Switzerland, can be found at: GHM-Team
Helena Schneider
Tax Consultant since 2001

Ms. Schneider has very wide experience in advising companies, self-employed professionals and private individuals on tax and business matters: her services here include preparing annual financial statements, net income statements and tax returns, as well as providing advice on real estate taxation. She also has valuable experience in drafting financial forecasts for tax purposes, in dealing with the inland revenue as a fiscal representative during tax audits, and in conducting appeal procedure both in and out of court.

After completing her studies at the University of Cologne, Ms. Schneider spent the first eight years of her professional career working for PVW GmbH Wirtschaftsprüfungsgesellschaft Steuerberatungsgesellschaft, an auditing and tax consultancy firm that cooperates closely with the international law firm Clifford Chance (Düsseldorf), before transferring to the tax consultancy Advisio & Tombers Steuerberatungsgesellschaft mbH (formerly Tombers Steuerberatungsgesellschaft mbH) and the auditing firm Advisio Treuhand und Revision KG Wirtschaftsprüfungsgesellschaft Steuerberatungsgesellschaft (Advisio Group, based in Gummersbach / Cologne), where she worked for ten years.