Ask any successful entrepreneur about the key to his or her success, and confidence is likely to be near the top of the list. That’s because entrepreneurs must be independent while connecting with the right people, level headed while taking risks, and big-dreamers while being utterly realistic about their prospects—all of which are fueled by self-confidence. Conventional wisdom says that confidence is something you’re born with or learn early. But the fact is that confidence can be achieved through effort and determination. Here are four concrete ways to increase your confidence, and therefore your possibilities, productivity and success as an entrepreneur. 1. Rid your life of negativity. If you want to live a positive, joyful life, you cannot surround yourself with negative people who don’t support or encourage your happiness. There will always be consistently negative people who constantly try to bring you down. Don’t allow these people to sap your confidence. This ma...