Melissa (LifeFullyBooked) Yes, I think you should. The many characters carry through each book and you need to get a sense of who they are and how they all fit together. There's quite a bit of back story given, so you won't be totally lost, but it will be missing something.
Maura This really doesn't work well as a stand-alone. Without any emotional investment in the many, many characters in the book, there won't be much reason to follow along. It's really just a continuation of earlier books with a new character introduced. I think I'd have DNF'd if I hadn't read the earlier books and wanted to catch up on the familiar characters.