In this edition of The Motley Fool's "Ask a Fool" series, Motley Fool analysts Jason Moser and Brendan Mathews take a question from a reader who writes:

Hello, I'm new to TMF and really enjoying it. I love the philosophy of buying long term and investing in companies, not the market. However, there may be reasons to want to sell, and I can't seem to find any guidance on that.

Selling is one of the toughest parts of investing, because it can be really hard to figure out when a stock has done all it can do. Sometimes investors may have better ideas for their money. Or perhaps the investing thesis has changed. And don't forget one of the main reasons for investing in the first place: to help secure your financial freedom. That means at some point you'll probably have to sell in order to use some of that money to live. So there are plenty of reasons to sell, and everyone's situation is different. But don't forget that often (but not always) when you do sell there will be tax implications to consider. So make sure you're aware of those before pulling the trigger.