Leveson's fantastic Therac-25 paper is probably the most important document in the formative years of my young sweng career.

I still re-read it every couple of years, and it's held up a lot better than one of my other early favorites, which was Feynman's appendix to the Challenger report. In the sense that I still draw new thoughts and realizations from it as I re-read it with additional experience in some of the engineering and organizational disciplines it touches. Sad as it is, it's got a little bit of everything.

It's definitely got my vote for the I Ching of critical systems engineering.

Spend the time. Chances are you'll remember it.