SPECIAL VOLUME IN HONOUR OF WALTER THOLEN ON THE OCCASION OF HIS SIXTIETH BIRTHDAY Walter Tholen will celebrate his 60th birthday this October,and there will be a special volume of Theory and Applications of Categories dedicated to this occasion. The deadline for submission is 15 March 2008. For more information, please visit the web page http://www.mat.uc.pt/~cmatcs/WTholen_volume.html The Guest Editors, Maria Manuel Clementino, George Janelidze, Robert Rosebrugh, Jirí Rosicky