It's been said that one of the keys to successful investing is not putting all your eggs in one basket – also known as diversification. So, you'd assume that investing in an index such as the S&P 500 would protect you, right? Well, not necessarily! Wes brings to light that about a quarter of the S&P's total value is made up of just 6 companies, and he explains what steps you can take to make sure you aren't putting all of your eggs in one basket.