In recent months, for various reasons, not only in preparation for this colloquium, I have been deeply engaged with Ernst Forsthoff. I have repeatedly asked myself the question, what remains. We asked this question already in 1974 after his death, and we ask it again today on his 100th birthday. The answer: for us, who knew and experienced him, to whom many of us owe so much, what remains is the memory of a venerable person as well as the remembrance of a great German jurist of the 20th century. This volume, with which the publisher Duncker & Humblot honors one of its authors, who co-edited the journal "Die Verwaltung" there from 1968 until his death in 1974, as well as the festschrift for Carl Schmitt on his 70th and 80th birthdays in 1959 and 1968.