Cassia has been looking forward to her Match banquet for 17 years, and is thrilled to be matched on her birthday. Doubly thrilled to be matched to her best friend, Xander. When she opens her match files the next morning, though, she finds Xander's information--but also someone else's. Cassia had never really noticed Ky before--not in that way, anyway--and her curiosity is piqued. When an Official corners her the next day and confesses that it was a mistake, that Ky was never meant to be entered in the Match pool, Cassia's curiosity increases. As she and Ky spend more time together and get to know each other, she finds herself falling for him, asking questions, and generally bristling under the Society. 
 The Society demands conformity and does not tolerate questions, and free will isn't even a thing, really--there are no choices to be made; citizens are assigned everything from lunches to jobs to life partners [all hetero, incidentally; you're apparently allowed to choose singlehood but it seems odd that that would be the only choice they're allowed to make?]. 
 Definite overtones of The Giver and pretty much every "do I go for the steady reliable boy or the Bad Boy" romance novel, of which I'm sure there are about a zillion but only Colasanti's When It Happens is the only one springing to mind because I really don't read a lot of romance. 
 Something in the writing put me off this; maybe it was that Cassia's parents were never called "Mom" or "Dad" but always "my mother" or "my father"? Maybe Cassia's abrupt shift from Do What The Officials Say And Ask No Questions to WTF Are They Doing Let's Change Society? I dunno. Maybe I'm just too not-into the romance angle to enjoy this properly, but it's a great suggestion for girls who hate sci-fi when the sci-fi book report comes around.