Dear all, Prof. Doaitse Swierstra is retiring on August 1 of this year, and is leaving the very functional programming minded Software Technology group that he has led for many decades. We have compiled a Liber Amicorum in his honour that we handed to him after his farewell speech on May 30th. You can find a download of this book at: http://www.cs.uu.nl/people/jur/liberdoaitseswierstra.pdf Not all contributions are ``technical'', and not all of them are in English, but counting up the pages, I guess about 75 percent is. best, Jurriaan Hage