Among the Betrayed is a 2002 novel by Margaret Peterson Haddix, about a time in which drastic measures have been taken to quell overpopulation. It is the third of seven novels in the Shadow Children

Shadow Children sequence

The Shadow Children series is a series of seven books by Margaret Peterson Haddix about a futuristic country which suffers food shortages due to a drought and the effects of the government's attempts to control resources as a way to solidify its power...

series.
Among the Betrayed is the third book in the Shadow Children series. Unlike the first, it is not told from the viewpoint of Luke Garner, but rather from that of Nina Idi, the shadow child who was arrested with Jason Barstow at the end of Among the Impostors.