When a sports team is going bad, you'll often hear the manager talk about going "back to the fundamentals." In baseball, for example, that means see the ball, hit the ball, see the ball, catch the ball. In football it might mean reminding a receiver that you can't run with the ball until you've actually caught it. It's not as if the players don't know the fundamentals, it's more that they get distracted, or try to do too much at once, or lose focus when the pressure is on.
So it is in business. I can just imagine a manager at some level of a company being taken aside by his boss who says, "Things haven't been going well lately. We need to get back to the fundamentals. Read this." And the manager receives a copy of Ram Charan's latest book, Know-How.
Know-How is a book that does a nice job of boiling down success as a business leader into eight skills, things you must "know how" to do to be effective. None of the skills Charan highlights is going to give you an "a-ha!" moment, but they give you an "oh yeah" moment, as in, "Oh, yeah, I knew I should have been doing that all along, but got so caught up with X and Y that I forgot Z." In this way, it's a good book to keep around to gauge how your leadership is progressing against these bedrock benchmarks.
Here's what I mean by the fundamentals. In a (long) sentence, Know-How teaches that in order to succeed, a leader must position a business or department correctly, must set priorities well in order to reach correct goals that are attainable, must manage people well in order to keep them motivated and "with the program," and must be alert to outside factors that present both risks and opportunities.