Circle of Competence and Sector Concentration.

If you are investing within your cicle of competence, your stock selections will gravitate toward certain sectors and investment styles.

Following the fat-pitch strategy, you will naturally be overweight in some areas you know well and have found an abundance of good businesses.

Likewise, you may avoid other areas where you don't know much or find it difficult to locate good businesses.

However, if all your stocks are in one sector, you may want to think about the effects that could have on your portfolio.