Many middle class individuals believe that the goal in life is to be debt-free. When you reach the upper echelons of finance, however, that idea is almost anathema. Many of the most successful companies in the world base their capital structure on one simple consideration: the cost of capital. If you can borrow money at 7% for 30 years in a world of 3% inflation and reinvest it in core operations at 15%, you would be wise to consider at least 40% to 50% in debt capital in your overall capital structure. Of course, how much debt you take on comes down to how secure the revenues your business generates are - if you sell an indispensable product that people simply must have, the debt will be much lower risk than if you operate a theme park in a tourist town at the height of a boom market. Again, this is where managerial talent, experience, and wisdom comes into play. The great managers have a knack for consistently lowering their weighted average cost of capital by increasing productivity, seeking out higher return products, and more. To truly understand the idea of capital structure, you need to take a few moments to read Return on Equity: The DuPont Model to understand how the capital structure represents one of the three components in determining the rate of return a company will earn on the money its owners have invested in it. Whether you own a doughnut shop or are considering investing in publicly traded stocks, it's knowledge you simply must have. Question on our