In my private files, I have a note from Dorothy Denning saying that she enjoyed my 1998 book on intrusion detection. If you live in the security industry, then you’ll know that this is like having Einstein tell you he liked your physics paper. Professor Denning was the first, for example, to show that activity timelines could identify anomalies from normal behavior. Her 1987 IDES paper remains iconic reading for all students studying cyber security.