Okay, so let me explain how I read these books. I read the first book, "The Selection", and then the second, "The Elite", before the third book, "The One", had been published for the public. So I waited a few months for it to come out, heard about two companion novellas that were being published as well and was interested, but I couldn't order them until they were of course published. Months after these were released I FINALLY purchased them through Barnes & Noble and a few weeks later they arrived. At that time, I was engrossed in The Mortal Instrument Series by Cassandra Clare, so I had to put off reading the /mostly/ completed series. Around last week, I picked up the first novella "The Prince", read that, then the first novel, followed by the second novel, THEN the second novella "The Guard", and then the book I had been dying to read for months. Let me just say that this series is not just a princess-prince, fairy tale love story. There is so much drama, and action, the complex characters leave you wondering who she'll choose at the end of the story. I think Kiera did an amazing job at balancing out the romance with the action, the cheesy moments with serious ones that make you stop for a moment. Definitely a recommended series. Below is the list of the series in order, along with more books in the series being published:
"The Prince" novella (#0.5)
"The Selection" (#1)
"The Elite" (#2)
"The Guard" novella (#2.5)
"The One" (#3)
"The Favorite" novella (To Be Published)
"The Queen" novella (To Be Published)
"The Heir" (#4~To Be Published)