One big idea: make simple checklists for important, but easy to forget processes. It'll reduce your errors, and free up your brain to think about the harder parts of the problems you're solving.

I'd have rated it higher if there were more guidance on how much is "enough" in writing a good checklist, or if it were even shorter. Gawande goes back and forth between medicine and aviation in his examples, and he could perhaps consolidate the narratives a bit better.