WADT 2010 is put into perspective by giving afterglows of the 1
WADT 1982 in Langscheid near Dortmund, and the 10
WADT 1994 in Santa Margherita near Genova. First encounters with pioneers in the field are recalled, in particular with the ADJ group who initiated the initial-algebra approach. The author’s contributions at that time are put in this context. Around 1982, the emphasis of his work moved to databases and information systems, in particular conceptual modeling. His group used a triple of layers to model information systems, data—objects—systems, where the focus of interest now was on objects and systems. The interest in data issues paled in comparison. There were cases, however, where benefits could be drawn from the early work on ADTs and the foundations established in this field.