I picked up "Cry Wolf" by Patricia Briggs almost by accident, after seeing a reference to it in a review of a different book. It took me a chapter or two to realize that I was missing something, and this novella is the reason. 
 Although "Cry Wolf" is identified on Amazon and elsewhere as book one in the Alpha & Omega series, the action in CW is preceded by the events in the Alpha & Omega novella. The novella sets the stage for the A&O series, by showing how main characters Anna and Charles meet, explaining Anna's backstory, and setting events in motion for the series to come. 
 I suppose you could read CW without first reading the A&O novella, but I'd recommend starting here first.