Magic and the Modern Girl by Mindy Klasky
I just love this series of books by Klasky, featuring DC librarian Jane Madison who just happens to be a witch. ;-)
In this, the third novel, Jane finds her power diminishing from lack of use, and must summon her family, her warder (the hunky David) and her familiar (the always snarky, always opinionated Neko) to help her get her powers back. But when a spell goes awry, all of DC is turned upside down...
Not to mention, Jane has a new man vying for her affection, but how will David feel about that? ;-)
This is just a fun, fast to read, satisfying series about magic, libraries (woot!), the power of a good mojito and baked goods, and friends and family who stand by you, no matter what magical mischief arises. I can't wait for There's the Rub, the next book!