This review was first posted on http://www.rubysreads.com. 
 I'll be honest: I haven't had a great deal of success with Maria V. Snyder. I've started both the Study and the Glass series without the compulsion to finish them. Yet, I grabbed Inside Out the moment it hit the shelves. I've got a well-established love of the first person point of view, and Snyder sure knows how to satisfy it. I invariably like her heroines, and I think it's in large part due to their internal dialog. Snyder's heroines are smart, feisty and independent. These three things describe Outside In's Trella to a T. Especially if you add "slow to forgive" to the descriptive pile. 
 Speaking of Trella, she is at once an alluring and repulsive heroine. She's that girl that draws people to her because of her very aloofness. She'd be the kind of friend you'd be afraid to confide in because neediness scares her off. Though she interacts with others, Trella's a loner at heart. She's not interested in having people depend on her. Reluctance to get involved is both her greatest flaw and her biggest attraction. She excells at playing hard to get, because she doesn't even need to try. 
 In part, Trella is reluctant to take part because she doesn't want to let people down. She'd rather do nothing than try and fail. Also, I never got the sense that--apart from Riley--she ever really liked anyone. I suspect that Trella will never do friendships. Even at the end of the book she remains closed off. Which is a good trait for a leader, I suppose, but rather lousy in a friend or romantic partner. Though Riley takes a stab at pointing all of this out to Trella--and I admit that he has some sort of success--it's an indelible aspect of her character. And I can't help it--that turns me off. 
 Trella's loner-by-nature perspective also means that we don't get to know many of the other characters very well. Riley's not even in this one very much. We see Trella's possible birth mother, Lamont, and theirs is really the relationship that makes the most strides, and all of that is due to changes in Trella's perspective. 
 If Outside In has a message, it's that community is important. So is working together. The book is also strong on the message that it's important not to blur the line between you and your enemy. I don't mean that you shouldn't interact with them--but that you should be clear that the things that make a group an enemy are their actions. If Mr. X is your enemy because he tortures you when he has the upper hand, how are you any better if you do the same to him when the positions are reversed? 
 I can't, of course, write a review of a book and not mention the romance. I said that we see less of Riley in this book, but what we do see of him, I like. In Riley and Trella's relationship, he's the one that isn't afraid to admit his feelings. Usually (and stereotypically), it's the guy that holds back. Riley doesn't. His chemistry with Trella is believable and the shower scene--hot--especially for a Teen book. I felt for him, though, because it would be hard to love someone like Trella. She returns his feelings, but she's also completely dedicated to doing the right thing, even if it places her in danger. Which it does. A lot. Trella is hurt and hurt and hurt again in this book. I'm frankly surprised she made it to the end. 
 I enjoyed getting to return to Inside once again, and to learn a bit more about their world. For me, one of the most fascinating aspects of Dystopian fiction is watching people try to restore order. In the first book, there's a revolution. In the second book, we get to see the Insiders dealing with the aftermath, and fighting a new enemy. I don't know if Snyder is going to right another installment in the series--I rather doubt it, given the ending--but I'd be thrilled to read a book that was about the trials of turning a Dystopia into a better world. Not necessarily a Utopia, but something better than before.