He is a habilitated doctor of legal science, professor of law at the Łazarski University, which according to different rankings has been running the best legal department amongst non-public schools in Poland. He is an attorney and tax advisor, an author of scientific and popular science articles from the domain of public finance, tax law. He was the chairman of the Supervisory Board of ZUS (Social Insurance Institution), an advisor to the Prime Minister Kazimierz Marcinkiewicz, an advisor to the Minister of Finance Zyta Gilowska. He prepared expert opinions for the Bureau of Researchof the Sejm. He also advised to some of the biggest Polish companies such as PKN Orlen, LOTOS Group, PGNiG, Azoty Group, international investors and many private entities from the SME sector. Moreover, as an arbiter he participated in disputes resolution before arbitration courts with the Polish Chamber of Commerce, Polish Banking Association and by the ICC International Court of Arbitration in Paris. He sits as an independent member in supervisory boards of several stock-listed companies. Finally, he is the author of the book „Podatek progresywny a proporcjonalny. Doktrynalne przesłanki, praktyczne konsekwencje”.