It is with great sadness that we announce that Klaus Mackscheidt passed away on 10 November 2023. With his demise, the University of Cologne has lost a passionate academic teacher, a great economist and an even greater person. We will miss him dearly. In 2023, Klaus Mackscheidt had been Director at the FiFo Institute for Public Economics for 50 years. He celebrated this unique anniversary, modest and tireless as ever, with unflagging productivity. His last two essays "Klimaschutz und Wohnungsbedarf" and "Sondervermögen versus Schuldenbremse" are published posthumously as FiFo Discussion Papers.