Book excerpt: This Festschrift volume is published to honour both Dines Bjørner and Zhou Chaochen on the occasion of their 70th birthdays. The volume includes 25 refereed papers by leading researchers, current and former colleagues, who congregated at a celebratory symposium held in Macao, China, in the course of the International Colloquium on Theoretical Aspects of Computing, ICTAC 2007. The papers cover a broad spectrum of subjects.