Professor Kromer is the Director of the Business & Taxes Duel/Trio B.Sc Study Program and is a lecturer for Taxes in both B.Sc and M.Sc Study Programs. The expertise of Professor Kromer is in the areas of International Tax and IT, which includes Tax Strategies, Risk Management, Transfer Pricing, Tax Compliance Organization, Tax Accounting, and Tax Reporting Systems. These competencies come from years of leadership positions in Euro Stoxx 50, Big 4 and International Law & Tax Advisory Firms. While the University in Aachen developed expert decision-making software systems to assist charter tax advisors, Professor Kromer took part in the development. It continues to include expert systems that involve AI and has worked for KPMG with an intelligent questionnaire, which is a form of AI expert system.