Whether or not you're a natural born leader or you've just found yourself in a leadership role. You have to develop your leadership skills, and often.

No matter how much of a master Tom Brady is at throwing a football, he still goes to practice every day, takes coaching and evolves his skills. Your leadership skills are no different. They take deliberate practice/experience to refine, improve and acquire skills.

The six books below are ones that I go back to often to draw inspiration from in my own leadership development. They contain tales of resilience, sacrifice, and responsibility, and all give valuable leaderships lessons.

Meditations by Marcus Aurelius

While emperor of the Roman Empire (161 to 180 AD), Marcus Aurelius kept a personal diary. This diary, which has been translated into modern text has become one of the core reading materials for anyone interested in stoicism. Aurelius was the most powerful person in the world, facing issue after issue yet his writing shows how he dealt with the day-to-day of being the emperor of Rome. In Meditations, through his reflection, you are able to learn useful leadership lessons to apply to your business.

If your business goes through a rough patch, this book will be one that helps you with developing the right mindset to persevere through it.

Extreme Ownership: How U.S. Navy SEALs Lead and Win by Jocko Willink and Leif Babin

Navy SEALs know a thing or two about leadership. Jocko Willink and Leif Babin detail their experiences in Iraq, lessons learned and how they've applied these lessons to the corporate world as consultants. This book will teach you, as the leader of your organization to take complete responsibility for every part of your business and give you useful tactics right from SEAL training you can start to work on.

Leaders Eat Last by Simon Sinek

Simon Sinek became widely popular through his TEDx talk on how great leaders inspire action. However, in his latest book, Leaders Eat Last, Simon looks at the psychology of strong leaders and why people decide to follow them. Remember, you don't choose to lead anyone, people have to choose to follow you. This book will help you understand how to become more empathetic and how to accept responsibility for any of the business' mishaps.

Long Walk to Freedom by Nelson Mandela

Though, technically not a business book, The Long Walk to Freedom is the autobiography of the one of the most revered leaders of all-time, Nelson Mandela. Not only is this book filled with history lessons, it will teach you that true leadership takes conviction and a commitment to a vision/life's goal. You will walk away from this read with a deeper sense of what sacrifice really looks like to achieve greatness.

Losing My Virginity by Richard Branson

Branson's autobiography is filled with anecdotes, tales of adventure and business hurdles. This book will help you with understanding taking chances in business. They say good leaders follow the rules and great leaders know when to break them, this book only fuels that saying.

The Art of War by Sun Tzu

Now, your company is not at real war, however, it's in competition with many other players in the market, and people who are planning to disrupt your company. The Art of War is a short read, which helps with strategy and optics. It will reframe how you approach certain marketing, sales, and operational strategy.