Abhorsen Trilogy by Garth Nix
Garth Nix's Abhorsen Trilogy (Sabriel, Lirael, and Abhorsen) is set in a world that in some ways is very much like our own. The norther border of Ancelstierre (an England-like country), however, is heavily fortified because beyond its wall is the Old Kingdom, a land where magic is both commonplace and dangerous.
While Charter Magic is a force that unites and stabilizes the Old Kingdom, Free Magic (and those who wield it unscrupulously) has the potential to tear it apart. A guardian of the Charter, the Abhorsen's powers blend both Free and Charter Magic. A special kind of necromancer, the Abhorsen doesn't bring the dead to life, but banishes them further and finally into Death.
I really enjoyed the Abhorsen books. They are engaging and fast-paced. The books' target audience is young adult and their protagonists are all teens (well, Lirael's protagonists appear as adult secondary characters in the other two books). The world that Nix creates is what makes the series stand out. Not only does Nix imagine the Old Kingdom and all of its mythos, but the texture of Death itself.
One of the things that was most interesting to me is that while Lirael and Abhorsen are clearly part of a series (Lirael ends with a horrible cliff-hanger), Sabriel (the 1st book) reads like a stand-alone novel. I wonder whether Nix wrote Sabriel as a stand-alone and then wrote the other two when the first was well received.