Mr. Ostermueller has been in the professional practice of accounting, management consulting, business brokerage/M&A, and independent appraisal since 1962. He has served as Senior Manager, Director, Department Head, Consultant and Senior Staff for three national/international CPA and management consulting firms, owned and operated a small business brokerage in St. Louis, and was the Chief Financial Officer for a five-bank group in Oklahoma.

In addition to being certified and licensed as a CPA in Missouri, Mr. Ostermueller is also certified as an Accredited Senior Member of the American Society of Appraisers (ASA) - Business Valuation and Intangibles, an Accredited Business Valuer (ABV) by the American Institute of CPAs, and as a Certified Business Appraiser (CBA), by the Institute of Business Appraisers. He earned these designations by successfully passing each of their uniform comprehensive examinations in appraisal ethics and principles and in general/business valuation, appraisal theory and practice and/or by having two of his actual business valuation reports technically reviewed and passed by an examining member(s) of the respective business valuation professional society(s).

Further, Mr. Ostermueller is a past member of the Business Valuation Subcommittee of the American Institute of Certified Public Accountants (AICPA) and he has served multiple terms as Chairperson of the statewide Litigation Services Committee and of the Public Relations Committee for the Missouri Society of Certified Public Accountants (MSCPA). He has been admitted as a Practicing Member of the Academy of Experts (MAE) in London, England, and is also a Certified Fraud Examiner (CFE).

Mr. Ostermueller's clients include closely held business owners (and prospective owners), and their CPA/attorney professionals, whom he has served in valuation, sale, merger and acquisition matters for many years. His expertise in the area of business valuations, executive and other position evaluation and compensation systems, discovery/evidentiary/ forensic techniques and projection/compilation of economic damages has resulted in his being called as an expert witness in a variety of court and other legal proceedings in the U.S. and Canada.

Mr. Ostermueller was a member of the AICPA's Business Valuations Subcommittee, where he was the Task Force Leader for ABV Member Benefits. Mr. Ostermueller has been an Instructor in the ASA's and AICPA's respective business valuation certification programs and he serves (or has served) as a guest lecturer/instructor for the AICPA's BV courses to the Federal Judicial Center in Washingto, D.C., the U.S. Small Business Administration, the University of Missouri, St. Louis University and Lindenwood University, as well as for several professional and civic organizations and associations. He has also served multiple terms on the AICPA/ABV Examination Questions Sub-Committee.

He has served as a CBA Candidate Mentor for the IBA and was a member of the ASA's International Board of Examiners. Those responsibilities include reviewing CBA and ASA - Business Valuation candidates' written tests, experience/education qualifications, and/or written business valuation reports, as a preface to their being awarded the CBA, AM and/or ASA designation.

Mr. Ostermueller is the author of Practitioners Publishing Company's COMPANION to the PPC Guide to Business Valuations – 1996, 1997 and 1998. The COMPANION is a multiple template-based software (Excel 7.0 & 5.0, Lotus 5.0 & 4.0, QuattroPro 5.0, and Lotus (DOS) 3.4 w/WYSIWYG), written to automate the BV process in this annual guide which has been designated as an Authoritative Publication by the ASA-BV Committee.

Mr. Ostermueller's newspaper column Expert Opinion has been published in multiple legal newspapers and his articles are also published in professional legal journals, including Lawyers Weekly, Expert Witness Supplement, in Massachusetts, Missouri, Michigan, Rhode Island, Virginia, and the Indiana Trial Lawyers Association publication, The Verdict.

He is a frequent lecturer on valuations of closely held companies and has authored the AICPA's MAP Series' section on Valuation/Appraisal of Closely Held Companies.