It's been a while since I read this. I will update the review upon a reread.
From what I recall, it's a collection of more than 60 of Asimov's nonfiction essays and his tricks of the trade. Each one is no more than a couple of pages. I like the analysis of different aspects of the scifi genre as well as writing and publishing in general.
I remember taking a few lessons from the essays such as basing a fictional story off of a scientific concept or principle. Fascinating stuff. An invaluable resource to read and keep around your personal library. ( )