The best book on leadership I’ve ever read. Former Navy SEALs Jocko Willink and Leif Babin distill the principals they honed in the battle of Ramadi and demonstrate their applicability to business. But it proves a small cognitive leap to realize these lessons extend beyond combat and business. This is a guide for life.

A common fallacy in leadership books is assuming the reader is the boss. CEO memoirs fall into this category, despite the often overwrought efforts to prove they don’t. Wielding power over others affects how they perceive you. Bosses often mistake this power for their own innate talent or charisma, making their advice less portable.

The second common fallacy is that everyone in your organization is reading the same book. Books like Radical Candor fall into this category. Great if everyone’s onboard, but try implementing radical candor as a middle manager in an organization that hasn’t bought into the program.

Extreme Ownership avoids both traps. The authors learned how to lead without authority the hard way, when they had to include Iraqi forces in their patrols. If you’re the only person in your organization who implements these concepts, you’ll improve yourself. The principals seem obvious, but implementing them proves challenging. Sublimating the ego takes discipline.

This is not a military memoir or combat manual. It’s a guide to becoming a more capable human.

As a leader, it’s not what you preach, it’s what you tolerate. When setting expectations, no matter what has been said or written, if substandard performance is accepted and no one is held accountable—if there are no consequences—that poor performance becomes the new standard.

Even though I was familiar, having read the book twice prior, this principal still struck me. Implementing it has proved the most worthwhile in both my professional and personal lives. It’s also proved the most challenging. But Jocko and Lief only promise simplicity, not ease. It takes practice, but should you adopt these concepts, you’ll see immediate returns on the investment.