Peter Tschentscher (* January 20, 1966 in Bremen) is a German physician (molecular biologist and laboratory physician) and politician (SPD). He has been First Mayor of the Free and Hanseatic City of Hamburg since March 28, 2018; in this capacity, he was Chairman of the Conference of Minister Presidents by rotation from October 2018 to September 2019.[1] He has also been President of the Bundesrat by rotation since November 1, 2022.[2] From March 2011 to March 2018, he was Finance Senator in the Scholz I and II Senates.