In my view it is the single most important programming book in existence. Yes, other books will teach you other, incredibly important things. Other books will teach you the specifics of one technology or another. Other books will open up your mind on the very nature of programming (especially learning functional programming). And other books will teach you all of the incredibly important stuff that isn't siting at a keyboard and typing in code. But personally I'd rather work with someone who thoroughly groks refactoring even over someone who thoroughly groks functional programming.
http://www.amazon.com/Refactoring-Improving-Design-Existing-...
In my view it is the single most important programming book in existence. Yes, other books will teach you other, incredibly important things. Other books will teach you the specifics of one technology or another. Other books will open up your mind on the very nature of programming (especially learning functional programming). And other books will teach you all of the incredibly important stuff that isn't siting at a keyboard and typing in code. But personally I'd rather work with someone who thoroughly groks refactoring even over someone who thoroughly groks functional programming.