 Throughout his career, he held numerous offices, in particular that of a judge of the former Swiss Federal Commission of Appeal on Public Charges and that of president to the Federal Expert Commission on "Rechtsformneutrale Besteuerung" (Taxation neutral to the form of incorporation).He also member of the expert group "Collaboration internationale en matière fiscale" (international collaboration in taxation matters), founded by the Swiss Federal Counsel in March 2009.He has published numerous books and articles in the field of Swiss and international tax law, in particular