Mercury, the planet of shopkeepers, becomes the planet of shoplifters (metaphorically speaking, at least) when it reverses direction in the sky.

Now, this doesn't mean that you'll be plagued by criminals walking off with your goods, but it does infer that mistaken assumptions, crossed signals, and wild misunderstandings could cost if you don't watch out.

That's why it's always a good idea to get things in writing when the messenger planet is retrograde; and if you can't get it in writing, then hold on to all receipts, texts, and email threads. You may need these to prove that a purchase wasn't delivered or went missing.

The plus side to Mercury traveling backward is that it gets you to go back the way you came. Like retracing your steps to find a lost object, Mercury forces us to revisit our customary approach to matters that we take for granted. Not only will we realize that it was counterproductive, we may even discover a better way of realizing our goals.

Mercury will be retrograde from December 12th to January 1st.